Resources from the National GAPs Program
There are 20 different easy-to-use sections. Simply download those that apply to your farm. You can do a farm self-assessment, set priorities, and come up with an action plan. Here are a few of the sections that may be most relevant to strawberry producers:
Toilets and Handwashing
Post Harvest Handling
On-Farm Decision Trees: Farm Food Safety Decision Making Made Easy
The purposes of the Decision Trees are to:
- Help you identify risks and practices that reduce risks;
- Prioritize the implementation of practices to use limited resources wisely;
- Familiarize you with the terms and methods necessary to understand and follow requirements and expectations for food safety from buyers, farm markets, schools, and federal regulations.
Begin with How to Use the Decision Trees and reviewing the Checklist to identify which Decision Tree you should complete first. There is a Glossary in case any terms are unfamiliar. All of the Decision Trees follow simple 'YES or NO' pathways to aid you in assessing your current practices.
- Worker Health, Hygiene, and Training
- Agricultural Water for Production
- Soil Amendments
- Wildlife and Animal Management
- Land Use
- Postharvest Water
- Sanitation and Postharvest Handling
Visit the National GAPs website to see the many things you can order, including posters on hand-washing and brochures and pamphlets in English and Spanish
Food Safety Resources
Audits and Cost Shares
Post Harvest Handling
- Best Handling Practices for Fresh Strawberries (California Strawberry Commission)
- Maintaining Post Harvest Quality (University of CA-Davis)
- Postharvest Handling of Fruits and Vegetables (NCSU)
- Maintain the Cold Chain (University of CA-Davis)
- Additional resources (NCSU)
Washing & Sanitizing Containers
Hand-washing Unit Options
- Portable Hand-washing Units (NCSU)
- Poly Portables (GA company that supplies portable toilets and handwashing facilities)
Insurance options for food safety
Employee training/ implementing
Best practices for display
- Production and Handling of Berries(Display and Unpacking info)
Choosing & Using Chlorine-Based Products
Websites for Technical Info, Other Organizations, Etc.
NCSU Strawberry Growers Information Portal
NCSU Cooperative Extension Service
NCSU Dept. of Horticultural Science
NC Agricultural Chemicals Manual
NCDA Agronomic Division (plant tissue sampling & analysis, soil sampling, nematode essays, etc)
Southeast Region Small Fruit Consortium
NCFARMFRESH The NC Department of Agriculture's website will list farms that sell direct to the public, both Pick Your Own and Ready Picked. Consumers can search the listings by county to find farms closest to them. Strawberry farm listings include phone numbers, directions, hours of operation, etc. To be listed, contact Kevin Hardison, NCDA.
Other Strawberry Organizations:
Good Information from Other States or National Organizations/Institutions
An Introduction to Commercial Strawerry Production (Penn State) http://extension.psu.edu/business/ag-
Resource LIst from the Agricultural Marketing Resource Center
Marketing informationfrom ATTRA, lots of good resources on direct marketing, value added, etc.
Websites of Suppliers to the Strawberry Industry
The following companies and service providers are members of the NC Strawberry Association. Other suppliers are members, but did not provide a web address. Contact the NCSA office if you need assistance locating suppliers.
Commercial strawberry plant sources
Aaron's Creek Farms strawberry plugs
Alliance Farm Group strawberry plugs
Cottle Strawberry Nursery strawberry plugs, tips, plants
Darnell Farms, plants
Fresh Pik Produce strawberry plugs, tips, plants
Jersey Asparagus Farms plugs
Lassen Canyon Nursery strawberry plants
Luc Lareault, Inc. strawberry plants
Nourse Farms dormant plants
Strawberry Tyme Farms fresh dug plants, tips
Triple J Nursery plugs
Virginia Berry Farm plugs
Also see the full plant supplier list in the Resources Section, which is updated each year in June.
Irrigation, Sprayers, Other Equipment
B. B Hobbs Co., irrigation
Berry Hill Irrigation, irrigation
Earthtec Solutions, soil moisture monitoring equipment
Gra-Mac Irrigation, irrigation equipment and supplies
H & H Farm Machine Co., sprayers
Johnson & Company, irrigation
Reddick Equipment Co., sprayers
Reddick Fumigants, fumigation equipment and supplies
Tri-State Distributors of Statesville, sprayers
Frost protection, row covers, protected culture
AutoVerters, row covers
Berry Hill Irrigation, row covers, thermometers, etc.
J & M Industries, row covers
Jersey Asparagus Farm, high tunnels
Haygrove Tunnels, high tunnels
Reddick Fumigants, row covers
Fertilizers, soil amendments, crop protectants
American Bionutrients, fertilizers
Arysta LifeScience, crop protectants
Earthtec Solutions, fertilizers
Eco-FX, fertility management
GroGreen Solutions, fertilizers
Helena Chemical, fertilizers, crop protectants, adjuvants
Novozymes--Natures Green-Releaf, nutritional products
Tiger Industries, fertilizers
UAP, fertilizers, crop protectants
Yara North America, fertilizers
Marketing Supplies, Processing
Baskpac Products, plastic baskets
Cottle Strawberry Nursery, plastic buckets
Dillman Farm, jams and preserves
D'Vine Foods, processing, private label products
Hillside Orchard Farms, processing, private label jams, juices
Industrial Container Corporation, packaging (many kinds)
Monte Package Co., packaging (many kinds)
Peninsula Packaging Company, packaging (plastic clamshells)
Southern Container Corporation of Wilson, packaging (many kinds)
East Carolina Farm Credit, agricultural financing
Coastal Plains Horticultural Enterprises, ag consulting
Royall Commercial Contractors, metal buildings
Small Farm Central, website management
Verti-Gro, container growing systems
Commercial plant sources websites:
Aaron's Creek Farms strawberry plugs
Alliance Farm Group strawberry plugs
Cottle Strawberry Nursery strawberry plugs, tips, plants
Darnell Farms, plants
Fresh Pik Produce strawberry plugs, tips, plants
Jersey Asparagus Farms plugs
Lassen Canyon Nursery strawberry plants
Luc Lareault, Inc. strawberry plants
Nourse Farms dormant plants
Strawberry Tyme Farms fresh dug plants, tips
Triple J Nursery plugs
Virginia Berry Farm plugs
Also see full plant supplier list in Resources Section, which is updated each year in June.
North Carolina Strawberry Farm websites:
Airport U-Pick, Elm City, NC
Bernie's Berries, Greensboro, NC
The Berry Patch, Robersonville, NC
Britt Farms, Mount Olive, NC
Brock Farms, Winterville, NC
Buckwheat Farm, Apex, NC
Carrigan Farm, Mooresville, NC
Country Road Strawberries, Pinnacle, NC
Cottle Farms, Faison, NC
DJ's Berry Patch, Apex, NC
D & L Farms, Chapel Hill, NC
Faucette Farms, Browns Summit, NC
Flat River Nursery, Timberlake, NC
Gross Farms, Sanford, NC
Hall Family Farm, Charlotte, NC
Ingram Farm, High Point, NC
Iseley Farms, Burlington, NC
Maple Springs Farm, Dallas, NC
McAdams Farm, Efland, NC
Miller's Strawberry Farm, Graham, NC
Oakley Farm, Chapel Hill,NC
Patterson Farm, China Grove, NC
Porter Farm & Nursery, Willow Springs, NC
Rudd Strawberry Farm, Greensboro, NC
Smith's Nursery & Strawberry Farm, Benson, NC
Southside Farms, Chocowinity, NC
Steeple Hill Farm, Summerfield, NC
Strawberries on 903, Winterville, NC
Tuckers Farm & Nursery, Madison, NC
Tuttle Berry & Vegetable Farm, Stoneville, NC
Vollmer Farm, Bunn, NC
Whitaker Farms & Greenhouses, Climax, NC
NCSA Member Strawberry Farms Outside North Carolina:
Berry Plantation, North Augusta, SC
Bush -N- Vine Farm, York, SC
Charpia Farms, Summerville, SC
Hardy's Berry Farm, Anderson, SC
Hunter Farm, Easley, SC
JL Belue Farms, Spartanburg, SC
Springs Farm, Fort Mill, SC
Strawberry Hill, USA, Chesnee, SC
Brookdale Farm, Virginia Beach, VA
Chesterfield Berry Farm, Mosley, VA
College Run Farms, Surry, VA
Cullipher Farm Market, Virginia Beach, VA
Flanagan Farms, Virginia Beach, VA
Lilley Farms & Nursery, Chesapeake, VA
Mackintosh Fruit & Berry Farm, Berryville, VA
Miller Farms Market, Locust Grove, VA
Mt. Olympus Berry Farm, Ruther Glenn, VA
Pungo Produce, Virginia Beach, VA
Vaughan Farms Produce, Virginia Beach, VA
Wegmeyer Farms, Hamilton, VA
Westmoreland Berry Farm, Oak Grove, VA
Calhoun Produce, Ashburn, GA
Color Burst, Grayson, GA
Lane Packing/Southern Orchards, Fort Valley, GA
Ottawa Farms, Bloomingdale, GA
Southern Belle Farm, McDonough, GA
Southern Grace Farms, Enigma, GA
The Strawberry Patch,Reynolds, GA
Twin Oaks Fun Farm, Forsyth, GA
Washington Farms, Athens, GA
Other States (alphabetized by state/province abbreviation, then farm name)
Alliance Farm Group, San Luis Obispo, CA
Pell Farms, Somers, CT
Fifer Orchards, Wyoming, DE
Berry Patch Farm, Nevada, IA
Mayneland Farm, Naperville, IL
Mrs. Heather's Strawberry Patch, Albany, LA
Nourse Farms, South Deerfield, MA
Harman's Farm Market, Churchville, MD
Oakley's Farm Market, Salisbury, MD
Shlagel Farms, Waldorf, MD
Polter Berry Farm, Fremont, OH
Stacy Family Farm, Marietta, OH
Heeman Farms, Thorndale, Ont
Strawberry Tyme Farms, Simcoe, Ont
Kuhn Orchards, Cashtown, PA
Bradley Koutry Acres & Greenhouse, Cottontown, TN
Green Acres Berry Farm, Milan, TN
McPeak Orchards, Pittsburg, TX
Sweet Berry Farms, Marble Falls, TX
Thompson Strawberry Farm, Bristol, WI
Strawberry Farm Field Trip Guide for Farmers
Before the field trip
- If the teacher does not request it, ask him/her to visit the farm – a teacher should never take a field trip (farm or otherwise) to a location s/he has have not personally visited prior to taking students.
- Arrange your schedule so you will have time to walk the same path at the farm you will take with the students and teachers.
- Explain where you want the group’s bus/cars to park, and what they should do on arrival.
- Discuss with the teacher what you will be showing/telling the students
- Ask the teacher if there are things s/he is particularly interested in having you share/show the students.
- Make sure the teacher is aware of things that may be safety concerns for you
- Discuss time frame – what time the group plans to arrive and leave
- Discuss lunch/snack plans if lunch/snack is to be at the farm
- Discuss bathroom accessibility
- Ask about students with special needs, make sure you are aware of those needs. For example, if there is a wheel chair-bound student, will s/he be able to visit all locations?
- Be mindful of not staying in one location too long. The more the group moves, the more students will be able to see and learn from this visit.
- Particularly if it is a warm day, if possible, make sure the group is in the shade as much as possible. You spend a lot more time in the sun than students do!
Day of Trip
Attempt to have your farm as neat and safe as possible.
When you can, soon after the trip
Check with the teachers and with your field-trip staff (if not yourself) about how you the logistics, content, and experience of your field trips can be improved in the future.
VIF Plastic Conservation Cost-share
Methyl Bromide Alternatives Conservation Cost-Share
Details on Fumigant Regulations on Respirators, Costshares, and Testing Services
Respirator Testing at the Preplant Meetings
Medical Questionnaire for Fumigant Handlers
Providers of Medical Clearance and Fit-Testing
Sign to Post at Fumigated Fields
Fumigation materials, regulations, and practices are changing rapidly at this time. Cost-share programs for using alternative fumigants to methyl bromide and using VIF plastic mulch are available to North Carolina growers through the Natural Resources Conservation Service in 2009 (availability for 2010 will be determined in Fall 2009).
Here are some resources relating to fumigation:
Lettuce-seed bioassay (to see if it safe to plant after fumigation)
North Carolina EQIP Conservation Program Guidelines (look under "North Carolina EQIP Technical Information"
RESOURCES FOR FUMIGATION, especially the new regulations
Details of Respirator Regulations, Costshares, and Testing- Explains what is required, what services are offered, and available costshares for respirator testing and purchase of respirators. This document was designed for 2011 Preplant meetings, but may still be helpful.
Providers of Medical Clearance and Fit-Testing is a list of companies and organizations across North Carolina and in Virginia that offer these services. If you are unable to get this done at a meeting sponsored by Extension, the NC Strawberry Association, or the NC Agrimedicine Institute, you can go directly to these companies.
Medical Clearance Questionnaire (designed for factories/workplaces, but for growers too). You can take this to your doctor if you do not use the online questionnaire.
New Fumigation Warning Signs are required to be posted at access points to your field. TriEst Ag, the major fumigant distributor in our area, has created and printed these signs. You should be able to get copies of these signs from your fumigant dealer or supplier or custom fumigator. Ask for them! NCDA has also developed an approved sign, but it is not yet printed in quantity. Here is a pdf file of the Fumigant Warning Sign developed by NCDA; you can download this file and take it to a local copy store and have copies printed. Signs must be in color (red and black) and be at least 14 x 16 inches in dimensions. It is a good idea to laminate your signs so they last longer. Follow label instructions about posting locations and the length of time signs must be left up.
EPA's Fumigant Toolbox contains templates for fumigant management plans, handler information sheets, product labels and much more. It is quite well organized.
A Fumigant Resources CD, containing those files from the EPA Toolbox that are relevant to the products used by most plasticulture strawberry producers in our region, plus additional resources (including many of the items above) is available. Contact NCSA.
Custom Work for Strawberries: Soil Fumigation, Plastic Bedding, and Drip Tape
List updated June, 2001. Check with individual applicators to make sure they have appropriate licensing for your state. Please call NCSA with any additions, changes, or deletions.
Caleco Soil Services, Inc.- Rocky Point, NC, 910-675-2394
Cottle Strawberry Nursery- Faison, NC, 910-267-4531
Hendrix & Dail- Greenville, NC, 800-662-4130
Reddick Fumigants, Inc.- Williamston, NC, 252-792-4615
Alan Sawyer- Liberty, NC, 336-685-9645
James Sharp- Sims, NC, 252-235-4485 or 4106
Ken West (Virginia only)- Ruther Glenn, VA, 804-448-2193, 804-370-8443 (mobile)
Mitchell Wrenn- Zebulon, NC, 919-269-4993 (day), 919-269-9781 (eve), 919-414-6836 (mobile)
Our Greenhouse Plug Production
By Danny McConnell, McConnell Farms
McConnell Farms, Inc., located in Henderson County in the mountains of western North Carolina, has been growing and changing for the last 50 years. Beginning as a 70-cow dairy started by my father, the farm has evolved from a dairy/row crop operation to the production of apples, vegetables, specialty crops, and strawberries. Just three years ago we expanded our greenhouse operation to include strawberry tip production based on micropropagated stock. Our new endeavor into plant production began as a necessity: we were unable to secure the quality and quantity of strawberry tips needed by our optimum field planting date of August 1.
After in-depth investigation into micropropagation and lengthy discussions with Zvezdana Pesic Van Esbroeck of the Micropropagation Unit at NCSU and officials from the N.C. Crop Improvement Association, we took a leap of faith and built a 2200-square foot greenhouse. The standards set by the N.C. Crop Improvement Association required a concrete floor and insect barriers. While these standards can seem very strict and cumbersome, we found that the extra expense and effort to meet them has more than paid off with a remarkable increase in plant and fruit quality.
As of our 2001 harvest we have produced two crops of Chandler berries grown from tips propagated from this house; the fruit and plant quality has proven to be excellent. Because of these high quality and healthy plants, we feel that the probability for successful carry-over of these plants is greater than with normal practices.
Our plants are raised in 4-inch PVC troughs. We started with 190 micro-propagated mother plants set four feet apart, then put the runners in the row until the plants were one foot apart. We now let the runners hang down and harvest the tips. From our current 1200 mother plants, we should harvest about 85,000 tips, enough for our farm and some to sell.
Our growing media consists exclusively of vermiculite and perlite so as not to run the risk of cross-contamination of the plants with any type of insect, disease, or nematodes that exist in many other types of growing media. In doing this we must "micro-manage" all nutrient solutions, watering intervals, and temperature regulation. Once the mother plants enter the house, tissue analysis and nutrient reports must be generated at close intervals to ensure healthy plants that will produce the maximum number of tips possible. NCDA Agronomist Steve Dillon has proven to be invaluable in this process.
The major difficulty for us has been developing the fertility program for greenhouse production of tips, and after Eric Bish's death we were pretty much on our own. I'd never dreamed the strawberry plant was so difficult to propagate! After three years of experience we have found a direct correlation between the nutrient solution given the mother plant and the speed at which the tips taken from the mother plants make sufficient root growth to sustain themselves as independent plants. Even now, every time we get a tissue analysis we're still adjusting the solution.
On January 10, 2001, our current mother plants were brought directly from the NCSU Micropropagation Lab to my greenhouse. To this date absolutely no type of fungicide or insecticide treatment of any kind has been applied to the plants, largely due to the strict standards for greenhouse construction imposed by N.C. Crop Improvement Association. Periodically NCSU Entomologist Jim Walgenbach inspects the house for insects and mites, and at his last visit in June no pests were found.
The micropropagation of strawberries in North Carolina is still in its infancy. Much research is still needed. Although the process is not cheap by any means, we feel that the benefits far outweigh the drawbacks. Our experience with micropropagationhas been very positive. As micropropagation has changed the face and the future of the strawberry industry, assuredly more positive changes are on the horizon, and McConnell Farms Inc. is committed being a part of that future.
This year, McConnell Farms will offer some of the plugs it produces for sale. (See plant supplier list in the Resources section of this website.)
Stinger Herbicide Now Registered for NC Strawberries
By David Monks, NCSU Dept. of Horticulture. Edited from an article in The Strawberry Grower, September 2003.
In late August, the herbicide Stinger was labeled for use by North Carolina strawberry growers. This has been a long process, but Stinger will be a valuable tool for our growers.
Stinger was developed by and is marketed by Dow AgroSciences for a number of crops, including strawberries. It is registered for the control of the following weeds: Jerusalem artichoke, clovers, common cocklebur, curly dock, dandelion, groundsel, jimsonweed, prickly lettuce, nightshade, common ragweed, giant ragweed, smartweed (suppression), red sorrel, sowthistle (suppression), sunflower, bull thistle (suppression), Canada thistle (suppression), and vetch.
Growers will need to sign a waiver of liability for the use of Stinger in strawberries in North Carolina before they can obtain a label and use the herbicide. Use of waivers like this is increasingly common in high value crops and with some herbicides. Dow AgroSciences would only agree to bring Stinger to market if there was a waiver to reduce their liability. The waiver program will be managed through the NC Strawberry Association. Growers must sign the waiver included in this newsletter, or request a waiver from the NC Strawberry Association, sign the waiver, and then return it to the NC Strawberry Association office. NCSAâ€™s Executive Secretary will then provide a copy of the label to you. You will also be able to sign the waiver at the Southeast Strawberry Expo and pick up a label there. The waiver and label will NOT be available from other sources, such as your farm supply dealer selling the product.
The critical information on Stinger use is provided on the Stinger label. Be sure to read the label prior to use.
Currently, Stinger is registered for strawberries in a few other states, including Ohio and New Jersey, but not the ones surrounding North Carolina.
Stinger been evaluated in our strawberry research since the early 1990s to support a possible registration in strawberries. One graduate student, Greg McMurray, spent several years researching the product in strawberries. Food crop registrations for Stinger have been developed through the IR-4 program, a program that is responsible for assisting with establishing tolerances of pesticides for minor use crops. This program establishes an EPA-approved protocol for field residue trials. Data is collected and then submitted to EPA for the purpose of establishing a tolerance. Once a tolerance is established, a label can be written.
In our Stinger research, several field sites were established. The strawberry plants were sprayed with Stinger, and as the crop matured, fruit were harvested and then trucked to a laboratory where residue of clopyralid, the active ingredient in Stinger, was evaluated. We presented our research results to a committee on campus responsible for making recommendations to the NC Department of Agriculture and Consumer Sciences with regard to the need of a state label for Stinger, and then NCDA&CS worked with Dow Agro-Sciences to develop the label for NC. More recently I assisted the company with writing and revising the Stinger label so that it suited NC production.
Our initial research with Stinger in strawberry was on Danny McLawhornâ€™s farm in Pitt County, NC. Our results at 1/3 pint Stinger per acre in plasticulture strawberries were 90% vetch control at four weeks after spraying, increasing to 100% at eight weeks after spraying. It did an excellent job not only controlling vetch growing from the hole in the plastic near the crop, but it also controlled the rest of the weed growing under the plastic. It was safe to the crop. Since then, we have conducted many trials, including a variety strawberry trial, each time demonstrating effective weed control.
Stinger is registered in plasticulture strawberries at 1/3 to 1/2 pint Stinger per acre. The rate can be increased to 2/3 pint Stinger per acre in row middles. Stinger is active only on specific weed species, thus it is not uncommon to observe species of weeds that are not affected by Stinger. Also, there are no grasses listed on the Stinger label; thus attempts to control specific broadleaf weeds growing in middles where ryegrass is growing should not affect ryegrass.
In matted row strawberry production, 1/3 pint per acre Stinger can be applied in spring, and/or 1/3 to 2/3 pints per acre post-harvest. Stinger can not be applied within 30 days of strawberry harvest.
One area of research this next year will be crop rotation, where other crops will be planted on the plastic following use of Stinger on strawberries to identify crops which can be safely planted following Stinger use. Our concern is that certain crops may be sensitive to Stinger.
The Occurrence of Colletotrichum Crown Rot on Chandler in N.C. Certified Strawberry Nurseries in 2005
By Dr. Zvezdana Pesic-VanEsbroeck, Dr. Robert Milholland, and Dr. Charles Averre, of the NCSU Micropropagation Unit, and Dr. Daryl Bowman, NC Crop Improvement Association
Strawberry crown rot caused by Colletotrichum gloeosporoides was found in several nurseries this year. The occurrence of this disease was very unfortunate but not totally surprising. The following questions and answers will help to explain its occurrence and what needs to be done to reduce the risk of its recurrence and the risk of other pathogens and pests.
What is the difference between C. gloeosporoides and C. acutatum?
C. gloeosporoides is one of four species of the fungus Colletotrichum found to infect strawberry in North Carolina, and is referred to as "Colletotrichum crown rot", while C. acutatum is referred to as "anthracnose fruit rot". C. gloeosporoides is capable of causing crown, runner, petiole, leaf, and fruit infections. Although it has been isolated from infected fruit, it is not a major fruit rotting pathogen on strawberry. The extent and seriousness of this species on strawberry is not fully known. It does, however, have the ability of killing plants when growing under favorable conditions (plug plants in the greenhouse, or heavy irrigation in the field). Studies conducted at NCSU in 1988-89 indicated that C. gloeosporoides was not isolated from any of 184 infected fruit of Chandler, whereas C. acutatum was isolated from all 184 infected fruit. However, C. gloeosporoides was isolated from 49 crowns and C. acutatum from 19 crowns of the 184 infected plants.
Unlike C. acutatum, C. gloeosporoides has a very wide host range (250 plant species), including various weeds (sicklepod), trees, wild and muscadine grapes, blueberries, and other fruit and vegetable crops.
C. acutatum is a major fruit rotter of strawberry and is referred to as "anthracnose fruit rot". It has a narrow host range. Crown infections have been observed, but it rarely kills plants. The major source of contamination is other infected strawberry plants. Symptoms on nursery plants are primarily runner and petiole lesions.
Why do the certified nurseries have this problem now?
The fungus was able to contaminate Chandler in one of the Registered nurseries in 2004. These plants had been inspected by NCCIA and certified to be free of crown, runner, petiole and leaf infections by C. gloeosporoides. Because only 0.1-0.5% of the plants apparently became infected from an outside source, it was virtually impossible to detect the disease in a one-acre field. This is especially true when the entire ground is covered with foliage.
Where did it come from?
This is not known for sure. However, we suspect that it came from infected sicklepod plants growing adjacent to the nursery. We do know that all of the Foundation plants derived from the Micropropagation Unit greenhouses and the Sandhills Research Station were free of C. gloeosporoides, and have been since the late 1950s. We do know that both registered and certified nurseries growing strawberry plants in North Carolina can become infected with C. gloeosporoides if precautions are not taken and protocols not strictly adhered to. For example, there are high and low risk nurseries in the certification program. Nurseries that purchase plants from sources that are not in the program are at high risk of introducing C. acutatum and other pathogens such as those that cause Phytophora root rot, angular leaf spot, and other diseases. Nurseries that purchase plants only through the certification program are at risk from C. gloeosporoides coming into the nursery from an outside source such as infected weeds or other host species. Additional measures are being taken to ensure that the repeat of Colletotrichum crown rot is greatly reduced in the future.
What is the likelihood that other nurseries will be affected or that infection will be found in other cultivars at these nurseries?
The risk is real. Thorough inspection and proper diagnosis of the pathogen is very important. We anticipate that workshops with nurseries and implementation of additional safeguards will reduce the risk of Colletotrichum crown rot in nurseries but will not eliminate it.
Why was it not prevented by the existing protocols?
We did not fully appreciate the risk of C. gloeosporoides infection from native weeds such as sicklepod and other plants.
What recommendations are being made to certified nurseries?
- Strictly adhere to the certification standards and the MPU Strawberry Operations Manual.
- Plant resistant crops around the nursery to prevent possible spread of C. gloeosporoides from susceptible hosts.
- Implement good weed control practices.
- Increase spacing of plants to avoid disease spread within a nursery and to be able to see possible symptoms of disease during inspections.
- Avoid plug plants grown in high watering cultures.
There is a real need to fund research on C. gloeosporoides to determine the extent of damage both in nurseries and fruiting field by this pathogen.
What are the recommendations for handling infection in fruit production fields?
Determine what type of anthracnose is involved. Handle plants only when dry. Promptly remove symptomatic plants by bagging and destroying them. Apply fungicides with proper equiment that will ensure covering the underside of leaves. A high pressure (200-400 PSI) hydraulic sprayer or mist blower properly used will do an excellent job. The selection and timing of fungicide applications which has been presented by Dr. Frank Louws at many grower meetings and written up in The Strawberry Grower should be followed.
How do growers know if their supplier has infected plants?
Strawberry plants infected with C. gloeosporoides cannot be sold as "certified". Nurseries (both Registered and Certified) with Chandler plants not showing crown or runner rot disease were certified. Those nurseries with Chandler plants showing disease symptoms either completely destroyed the plants or were not certified. All nurseries with infected plants that intended to sell Chandler plants were told to tell their buyers that the disease was found in their nursery. The nursery could inform the purchaser that the plants were in the certification program and meet the other requirements for certification (trueness-to-type, quality, freedom from exotic diseases and pests) but could not be certified because of the presence of Colletotrichum crown rot in the nursery. This only pertained to Chandler. Other cultivars were certified because they had no detectable C. gloeosporoides.
What nurseries were affected?
Plants infected with Collectotrichum crown rot have been discovered in. Chandler at several nurseries this year. At M&M Plant Farm and Fresh Pik Produce, plug plants of Chandler have shown the disease. At McNeil Farms, RG Plants, Shingleton Farms, and Lewis Nursery & Farms bare root plants and tips of Chandler have shown the disease.
Crown Rot Prevalent in 2001
Dr. Frank Louws, Department of Plant Pathology, North Carolina State University
Phytophthora crown rot is widespread this year within the state. Three years ago we had a few cases of the problem and there was a distinct link to plant source. However, last year, especially after Floyd, and this year, the problem appears more widespread and no single plant source can be identified as the problem. Why are we seeing more Phytophthora crown rot and what does it mean for our industry? The spread of the pathogen, Phytophthora cactorum, is probably distributed in a similar fashion as several of our other disease problems such as anthracnose and angular leaf spot. It can be associated with the plants that are distributed from one geographic location to another. However, unlike anthracnose and angular leaf spot, once the pathogen is introduced in a field, there is a high likelihood it can persist in the soil for years. This pathogen is a cousin to the pathogen that causes black shank in tobacco, a disease many in North Carolina are familiar with. It is a "water mold" and therefore is spread and favored by free-standing water. This pathogen can form structures called oospores that can persist in the soil for years. These oospores can germinate when a host is present and one of the life stages, zoospores, can swim in the water and encyst on strawberry roots. The pathogen then grows along the root and directly into the crown where it can cause considerable crown discoloration (Figure 1). If damage is no enough to stunt or kill the plant initially (in the fall or early spring) plants will suddenly collapse during hot weather and under a heavy fruit load because of extensive damage to the water conducting tissue between the roots and shoots (Figure 2).
WHAT TO DO?
We were very aggressive in working with growers last fall and spring to devise management strategies to limit plant losses. However, many growers are seeing problems now for the first time. Historically, the problem has been restricted to a few scattered plants within each acre. Regretfully, we are observing fields with a higher incidence. Some growers are still electing to apply Ridomil Gold EC through the drip line to limit plant losses. According to the label, an application during harvest is allowed (always follow the label for timing, rates and application methods). Ridomil is systemic and will be absorbed into the plant and carried in the water conducting tissues. It is "curative" if a plant is not heavily infected and if the strawberry can produce sufficient adventitious roots to support the crop load and transpiration water requirements. Because the fruit do not have stomata, they do not transpire and therefore a limited amount of water and Ridomil enters the fruit. The chemical accumulates in the roots, crown and ultimately the leaves. Many infected plants will continue to collapse after a Ridomil Gold application due to the extent of damage already incurred.
2005 Anthracnose Problems
By Dr. Frank J. Louws, Department of Plant Pathology, NCSU. From the September, 2005 Strawberry Grower newsletter
Anthracnose has been diagnosed during the last week (August 22-26) in two nurseries seeking certification from the North Carolina Crop Improvement Association. The occurrence of anthracnose in nursery stock is cause for concern for fruit producers. The affected nurseries have contacted their customers. The other certified nurseries in NC have been intensely inspected or will be (re-) inspected during the coming week to verify that their planting stock does not have the anthracnose problem. It appears that only a small percentage of nursery plants have been affected to date. Therefore, if your nursery supplier has not called you or cancelled your order, then it is highly probable that their plants have been inspected and certified. While this diagnosis is, of course, very disappointing news for these particular nursery suppliers, diagnosing the disease prior to distribution to fruit production farms should help avoid the difficult circumstance we encountered in 2004 when infected tips were widely distributed.
To date, it is not clear where the pathogen came from, but work has been initiated to help solve this question. The pathogen found in these nurseries was Colletotrichum gloeosporioides (Cg), while in more recent years in North Carolina the pathogen has been C. acutatum (Ca). The symptoms were rather widespread on Chandler plants in the nurseries, but cultivars such as Sweet Charlie and Bish had a low level or no apparent symptoms. The Chandlers had an uncommon but previous reported leaf spotting, lesions on the petioles and runners, and a low incidence of crown rot. The Cg strain is a more aggressive crown rotter and perhaps less aggressive in causing the ripe fruit rot phase. However, the pathogen can cause widespread damage to plants and fruit (come spring) and is best avoided.
Growers who were planning to use tips or bareroot plants from the affected nurseries are best advised to secure an alternative plant source. Several growers asked if it would be safe to use the Sweet Charlie and Bish tips from the affected nurseries since these do not seem to have symptoms. If these varieties were grown near the affected Chandler plants in the nursery, then these plants will have the pathogen on them even if they do not show symptoms. Therefore, using these tips would present a high risk. During the plug production phase, the continuous watering and warm temperatures will favor the anthracnose disease and it is likely that a high percentage of plugs of these varieties will die from the disease. In addition, introducing these tips onto the farm could introduce the pathogen, which then may spread to other varieties from other sources. The anthracnose pathogens are very capable of spreading from plant to plant, especially under greenhouse conditions due to misting, or are easily spread in outdoor operations through misting and wind-driven rains. If the plugs survive, then there may be a high incidence of crown rot in the field.
Use of fungicides has not proven effective during the plug production phase. There is very limited research on this, and heavy use of fungicides in the plug production phase is not allowed or not recommended. Therefore, it is better to secure an alternative source of tips rather than attempt to grow known infected tips and introduce a high risk of problems.
On the other hand, if these varieties are grown and the plants survive well, Sweet Charlie and Bish have superior ripe fruit rot resistance, so fruit losses in the spring would be lower than the losses experienced for Chandlers. For example, in our research trials during the spring of 2004, under heavy disease pressure conditions and no use of fungicides, Camarosa and Chandler had 61% and 58% anthracnose fruit rot whereas Bish had 12%. The fungicide programs that we have recommended have proven very effective and, when combined with resistance, offer acceptable levels of management of anthracnose ripe fruit rot. Thus, growers who cannot secure an alternative plant source, and wish to use these varieties, would need to adopt an aggressive IPM program and know that the level of risk, during the plug production phase and early field setting, is high. Such cases may best be handled on a case-by-case basis with your local Cooperative Extension personnel and NCSU specialists. We have specific protocols that can be followed.
Likewise, bareroot Sweet Charlie and Bish plants from these nurseries will present a high risk but may be the only option several growers have if an alternative source of plants cannot be secured. In such cases, plant dips may be useful. This will be explored in future newsletters if necessary.
Other Grower Questions
Q: Is there a threat to area strawberry operations near these nurseries?
A: The pathogen does not spread over long distances. Therefore, it is expected that growers near these nurseries (e.g. more than ½ mile) will not have anthracnose because the nursery does.
Q: What should the nurseries be doing to contain further spread?
A: The North Carolina Crop Improvement Association, the Micropropagation Unit, and NCSU personnel are working closely with the affected nursery suppliers to determine if such events can be avoided in future years. This article focuses on issues fruit producers need to consider.
Anthracnose Alert & Response
In the last few days of August, anthracnose was found in plugs from runner tips grown in Ontario, Canada. NC State University, the NC Strawberry Association, and plant suppliers are actively working to assess and deal with this problem. The following article is edited from Strawberry Plasticulture e-mail messages by Dr. Barclay Poling and Dr. Frank Louws on August 27 and September 1:
Over the last three days we have diagnosed anthracnose in several strawberry plug-production facilities. The problem does not appear to be restricted to one or a few operations but may be more widespread. It appears to be the Colletotrichum acutatum strain, which is typically associated with the anthracnose fruit rot and less commonly with plant collapse.
In a plug production facility, the problem appears to start as hot spots. Plants in such hot spots show a general unthriftiness, remain stunted, and are slightly discolored compared to neighboring symptomless plants. Such plants may resemble symptoms due to lack of water or high salts injury. As the disease progresses, one or more leaves wilt and the base of the leaf (petiole) becomes brown and wet. Advanced stages of the disease result in plant collapse. Botrytis crown rot and Pythium or Rhizoctonia crown rot may have similar symptoms. Therefore, it is essential that diseased plants be properly diagnosed. This involves incubating infected tissue for 24 hours and observing for characteristic spores and fungal structures. In some cases, we have isolated the pathogen.
If you have such a hotspot in the greenhouse, contact your local Cooperative Extension Agent and send samples to the Plant Disease and Insect Clinic according to the clinic instructions (http://www.ces.ncsu.edu/depts/ent/clinic/Submit/submit.htm).
This is very discouraging. There is nothing an individual grower could have done or should have done to prevent it-- it is a plant source problem. A similar problem was encountered last year with plant material propagated in Ontario from California stock plants in the spring and summer of 2002. Apparently, one of the main nursery suppliers in Ontario to the NC industry [Ghesquiere Farms] was unable to secure adequate micropropagated/certified planting stocks for planting this past spring, and California purple tags were (regrettably) utilized once again this season.
One difference from last year is the earliness of these outbreaks in Virginia and North Carolina plug propagation facilities -- the earliest symptoms of anthracnose were observed at about the end of the third week in the plug trays in 2002, but this year we are seeing it in the second week.
The best solution is to find an alternative source of plants. Some supplies of tips and fresh dug plants from sources that have no history of anthracnose are available (see the supplier update). However, it may be very difficult to locate an alternative supplier of tips or plugs at this late date. Most of the NC Certified plants were sold-out in late July.
Stick with normal planting dates. In many instances, growers who received infected material last year elected to find alternative plant supplies, but these efforts can also result in serious planting delays. Thus, it is paramount for growers to stick with their fumigation and planting schedules.
Investigating the problem
It is unlikely that these remaining supplies of fresh dugs from anthracnose free sources will hold out very long. The NC Strawberry Association has provided financial support for an immediate visit to the fresh dug fields of Ghesquiere Farms in Ontario, Canada. We will be looking for the obvious anthracnose symptoms such as slightly stunted plants and petiole and runner lesions. We will also attempt some sampling for the first time of plants that do not have the obvious symptoms. [Dr. Poling worked with Frank Louws to develop a plan for sampling the fields.] We have little research information on how to best sample symptomless plants, and as Frank has stated before, "a negative may not be a negative" meaning that we could literally test hundreds of plants and not find the organism at all. Yet, just one or two infected plants in the field can set off a very serious problem. However, we will still try to gather some preliminary data on sampling approaches from this visit. We will keep growers and agents advised of our trip and sampling results.
It is possible that the potential for anthracnose infection in a fresh-dug field planted with California stock is less than in tip and plug material, or at least that was the experience last year. The disease does not seem to show up as easily in fresh dug plants, and this may be related to the cooler conditions that prevail when these are dug in late Sept/Oct. in Canada. Tips are cut in the heat of summer and then rooted in even warmer greenhouses here in the Southeast --ideal for anthracnose expression. It would definitely be our preference for growers to use fresh dug plants that are apparently free of anthracnose infection vs. attempting to "make a go of it"with infected plug plants.
Using infected or potentially infected plugs
If an alternative source of plants is not a realistic option (as, for example, in September 2002, when water resources for irrigating fresh dugs didn't exist), immediately remove all infected trays and 1-2 sets of trays surrounding the infected area(s). Cull hard. Do not handle plants when wet and avoid touching healthy plants after handling suspected diseased plants. Minimize overhead watering.
Chemical control in late summer/fall was not shown to be effective in trials. In recent research we have not been able to confirm any benefit from late summer/fall applications of Quadris or Cabrio for controlling this disease in plug plants. Both of these products have been found effective for spring anthracnose fruit rot control, and it is likely that most or all sprays of these products should be reserved for the spring season. Again, our research did not show that Quadris or Cabrio sprays or drenches were effective treatments in the late summer/fall.
Growers who may wish to still apply these products at this time should know that the labels for Quadris and Cabrio would permit spray applications to plug plants in an outdoor setting, but not in a greenhouse. Don't apply sprays until after all infected trays and 1-2 sets of the trays surrounding the infected areas have been removed.
Further update September 1:
I [Barclay Poling] flew to Buffalo, NY, on Thursday morning, August 28, and rented a car to travel to Simcoe, Canada, for a two-day visit that included a review of the runner-tip fields and fresh dug plant production fields of Ghesquiere Farms. Mitchell Wrenn of Strawberry Hill Inc., and Gregg Gordon, Aaron's Creek Farms, also elected to fly up to Canada to get a firsthand understanding of the problem, as they work through this crisis with their customers and other nursery suppliers. I have been most impressed by the cooperative spirit of our nursery plant suppliers across the industry during this past week, and through the Labor Day weekend as they work to provide their customers with up-to-the-minute status reports on remaining plant supplies and options. One large nursery supplier (who is not experiencing disease problems at this moment), said to me last week that this current plant situation is "not good for any of us."
I began to receive a number of calls from concerned and anxious growers even before my return to Raleigh late Friday night. It is no wonder that they are anxious-- the investment in an acre of strawberry plasticulture is very high, and after a very disappointing 2003 spring strawberry crop for most growers, everyone wants to start the 2004 season off with anthracnose-free plants.
To recap the situation: The anthracnose infected plugs began showing up in NC, VA, and NJ last week. All of these plugs were propagated from runner tips grown and shipped by Ghesquiere Farms, Ontario, Canada in July and August. Apparently, according to the farm advisor I spoke with in Canada on Friday, the plants that produced these infected tips exhibited no symptoms of this disease during the summer at Ghesquiere Farms. Yet, we received positive confirmation of anthracnose in several samples sent to the NC Plant Disease and Insect Clinic by mid-week last week. One of these clinic reports was copied and shared with Mr. Ghesquiere and his farm advisor on Friday.
We collected a total of 800 leaf petioles from 800 different mother plants in two separate Chandler fields.
NOTE: Because the sampling technique being used for detecting anthracnose is so new, the University Office of Legal Affairs has issued this notice:
For growers who receive information about the source of plants in Canada that has anthracnose problems, you would need to qualify the information provided with the following points:
1. The strawberry specialist inspected fields that are of concern to inspect for proper disease management practices and visual signs of the disease. A representative sample of plants was obtained upon which laboratory examinations were conducted to determine if the disease was possible.
2. By the nature of the disease, it may be hidden at the time of visual and/or laboratory examination, and thus there is some risk that the disease may be present but not detected. Therefore, the risk of a false negative is relatively high.
3. We have done the in-field and laboratory screening to help reduce the risk to growers, but because the risk of false negatives is relatively high, the grower assumes risk for any disease that develops subsequent to the screening.
4. Therefore, our screening process in no way states or implies that plants are free from disease or the risk of developing disease.
This information should be provided IN WRITING to any grower who receives information regarding plants from the farm or farms of concern. (Aug. 29, 2003)
I did not see any obvious anthracnose symptoms in fields walked on Thursday afternoon and Friday morning. There were a few wet spots in each field where the plants did not runner that well--it has been a very wet summer in Ontario. I was most pleased with the high vigor and health exhibited by fresh-dug Chandler plants being grown at Ghesquiere Farms from a Canadian stock plant source which is using micropropagtion.
Frank Louws will soon be doing the laboratory screening of these samples, but we are still not going to be in a position to state that these plants are free from diseases or the risk of developing disease. As I said before, there is a real possibility of getting a "false negative." Despite very systematic sampling across two large symptomless Chandler fields (400 samples taken in each), we still may not have a large enough sample to detect the disease. Hopefully, if there is a problem in either field, it will be detected in these petioles, and we will relate this information as soon as possible. Everyone needs to appreciate that what we are doing is experimental and we will not be able to state or imply that these plants are free from disease, even if the samples are found to be negative.
Further News on Anthracnose
Funding Request: Besides funding Dr. PolingÃ¢â‚¬â„¢s trip to inspect the Ghesqhiere nursery, the NC Strawberry Association has requested that the NC Agricultural Research Service provide funds help deal with this incipient anthracnose crisis. Funds would go to Dr. Louws, for plant testing, to Dr. Poling, for educational programs for growers forced to switch from plugs to fresh-dugs, and to the NC Strawberry Certification Program, for continuing its work to create a NC-based clean plant program. NCSA asked $5,000 from the ARS and offered $3,000 from the AssociationÃ¢â‚¬â„¢s funds as a match. The ARS has responded, suggesting that funding might more appropriately through Cooperative Extension, but no action has been taken as yet , and the Association is interested in holding an emergency meeting withthe university in the next few days.
NC Certified Field Infection: Anthracnose was found in the field that one NC plant producer (Lewis Nursery) had in the NC certification program. Following the appropriate protocols, the field and its plants will not be certified. The nursery has notified its customers, helped them find alternate sources of plants, and pulled the plants off the market.
For Further News: Check the "Announcements" in the Members Only section of our Website for updates on the anthracnose situation, the plant supply, and other critical issues. We may also send out email info to our members--do we have your email address? Also, be sure that you are subscribed to the e-mail Strawberry Plasticulture newsletter put out by Dr. Poling, the source of much of this article and much other useful information for growers, both timely and free. You subscribe with an email. In the "To:" section of your email, write
In the "Message" section, write this message only:
and send it. That's all there is to it.
Best of luck to all growers struggling with a difficult situation. If there is some way the Association can be of assistance to you, please let us know!
Fall 2008 Strawberry Disease Observations and Recommendations
Frank Louws, Dept. of Plant Pathology, NC State University
The fall has been a challenge for many growers here in the South and for many of our nursery suppliers. In particular, excess rains have delayed fumigation and also provide a climate for the build-up of diseases. What are we seeing and what should growers consider?
PHYTOPHTHORA CROWN ROT, caused by Phytophthora cactorum, has become a recurrent, though not common problem in our industry. With the heavy rains experienced by some of our plant suppliers and wet soil conditions in many of our fields, growers should consider the use of Ridomil Gold in their planting beds. The label allows for the "first application after transplanting". It should not be used on plug plants prior to planting, as a dip, or in the transplant solution as these are not labeled uses and can cause plant stunting â€“ in our experience. Use 1 pt per treated acre (NOTE: Only half of an acre of strawberries is actually under plastic meaning 1 acre of land has 0.5 acres of treated area). It is best to apply Ridomil Gold after the time of excess watering and when the plants have taken a root-hold â€“ approximately 2 weeks after transplanting. Ridomil Gold is best applied through the drip irrigation system. Ridomil Gold is much more effective than the phosphorous acid generators (e.g. Aliette, Prophyt, Phostrol etc) for managing Phytophthora. The phosphorous acid generators are helpful in specific circumstances where Ridomil cannot be applied or when strawberry roots are severely damaged and a foliar spray of a product is the best option.
Manage fields to prevent standing water and saturated soils by channeling excess surface water to headlands and waterways.
In the past we have occasionally encountered Phytophthora problems in the plug production phase. This is a unique circumstance and treatment of plugs requires a different strategy. Contact your local extension office to get a sure diagnosis if plug problems are encountered.
For more information on Phytophthora problems and management see:
ANTHRACNOSE: We are not aware of any widespread problems with anthracnose at this time. Therefore, our recommendations are that growers should save their QoI fungicides (Abound, Cabrio and Pristine) for a spring program. If you are aware of a problem on your plants, then a specific management program can be developed on an as-needed basis. We are doing some lab research that may modify our spring fungicide recommendationsâ€¦stay tuned.
ANGULAR LEAF SPOT: Some incoming bare root plants have been diagnosed with angular leaf spot. Overall, this disease does not present a devastating effect. Yields are rarely affected. If frost protection is needed multiple times in the spring, and if we have a cool wet spring, then this disease can become an economic problem. Plant stunting and plant collapse may occur and as fruit mature, the calyx may get black triangular lesions. These black lesions make the berries look ugly and can affect retail sales. No products have shown benefit on a consistent basis and therefore recommendations for bactericidal sprays are not possible. Copper sprays may be useful in the spring and recommendations will be developed as the year progresses.
From March, 2001 Newsletter:
Suggestions for Growing Off-season Strawberries
By Sam Bellamy, Indigo Farm, Calabash, NC.
- Try to prepare yourself mentally. It is a lot of work and consistency is a must. One of the hardest adjustments is that you have to think opposite the season.
- Be prepared to "run" before you ever set the plants. With this crop it is crucial to start the plants going as soon as you get them.
- Be observant. Set goals for weekly, monthly progress to see if the plants are on course or if you can nurture better performance.
- Anticipate insect pressure, more so than in the springtime. The year 2000 has been kind in this regard so far. Perhaps this is due to the nice cold snap we had in early October. Usually, insects invade the setting quickly, especially after frosts.
- Fungal problems can be horrible under plastic, so be on the lookout. Remember you are creating a warm pleasant environment that insects and diseases find attractive.
- Bees can work all winter here, so think of them and encourage their help.
- Use a diverse and friendly spray program. You are going for a long haul. Encourage the good insects. Be prepared to hand-clean the field at least once in the winter for sanitation. There are limitations on most chemicals so you have to learn to use a wide assortment or find ways to minimize the need for chemicals.
- DON'T think of these strawberries as ordinary strawberries! They are special and rightly deserve to be "HOLIDAY BERRIES". You can't afford to sell them cheap.
- There is a lot of manual labor in growing off-season berries, especially in late December and winter. There may be some good reasons for shutting down all or part of your planting. This could have an effect on production and quality of the spring crop.
- You will have to monitor for spider mites throughout. They seem worse under plastic and they will sneak up on you. This can be very serious before you know it.
- I find vented plastic alone gives minor protection against low temperatures. Although it means more labor, I usually use a spun-bonded polyester row cover (like Reemay) as well.
- This year we are using a walk in tunnel to see if we can lower labor and to determine if low-temperature protection is enhanced.
June-July Growers Checklist
- Check field late in harvest season for diseases and insects, especially anthracnose.
- Send suspicious looking plants to the NC Plant Disease and Insect Clinic (free for NC; $25 fee for out-of-state).
- Spray strawberry plants 3 pints/acre Gramoxone to prepare for double cropping. Make sure chemical is labeled for use with the second crop.
- Remove and recycle plastic if not double cropping.
- Plant summer cover crop (e.g. millet or soybeans) or double-crop vegetables or melons.
- Decide now what varieties you will plant next fall and place orders as soon as possible.
- Clean up stand and coolers.
- Critique your 2001 season: Week-by-week sales? How you compared with the competition? Your branch crown numbers at the end of picking? What percentage PYO vs. Pre-pick? Don't hurry to plant a larger crop until you've evaluated 2001 results.
- Attend the Strawberry Pre-plant Meeting for your area.
- Pick those strawberries!
- Send in leaf samples every 14 days and adjust fertility accordingly. (See p. 4)
- Scout fields for mites, insects, and diseases. Respond as appropriate.
- Send suspicious looking plants to the NC Plant Disease and Insect Clinic (free for NC; $25 fee for out-of-state).
- Use drip to apply water as needed.
- Consider leaving overhead irrigation in field for evaporative cooling in hot weather. Turn irrigation on at around noon and turn off at about 3. Allow plenty of time in the afternoon for the leaves to dry off; you don't want to encourage the growth of disease.
- Start plants now for double cropping.
- Collect customer addresses and e-mails for future contact.
- Focus on customer service and marketing strategies. Run ads as needed to increase customer traffic.
- Remove and recycle plastic after harvest.
Signs of the Times? NC Growers Face Sign Restrictions
North Carolina growers have often faced problems with having their signs removed. This was particularly a problem in 2001, when NC DOT instituted some new, tougher regulations, though they have now moderated these. Local governments also remove signs in some areas. If you do have a problem, contact the Association as we may be able to help you.
- Check with your local municipality for its regulations. Try to develop a working relationship with your town/county government. Join the Chamber of Commerce and other organizations and participate in civic activities so you are a known member of the communith.
- There is no simple rule-of-thumb for all roads. You will need to inquire for specific situations. To find out for specific roads and sites, contact the highway maintenance garage in your county. It should be listed in the phone book under North Carolina, Division of Highways. You can also check the DOT website . This page shows a map of all the highway districts. Click on your district for a directory of your district office and the county maintenance offices within the district.
- Rights-of-way on two-lane secondary roads (names such as NC1234) are generally 60 ft. (30 ft. on each side of the center line).
- Signs placed on the far side of the ditches or outside utility/sign poles are usually okay. Utility poles are usually placed one or two feet inside the right-of-way.
- Where there is a curb and gutter, rights-of-way usually extend 10 feet behind the curb.
- Rights-of-way are larger at intersections. (For example, at a rural T-intersection, if you find the point two car-lengths back from the intersection in each direction, no signs can be placed within a "signt triangle" drawn between the three points.)
- Rights-of-way on primary roads (e.g. NC 55, US 64) that are four-lane or more may be as much as 250-350 feet.
- You cannot put temporary signs on interstate highways and other limited-access roads. Signs along these roads require permits and have many other requirements.
- You cannot tie signs to highway signs, staple them to utility posts, etc.
- Larger, more valuable signs are generally taken back to the county maintenance yard and held for a while before being discarded, says Steve Varnedoe, State Maintenance Engineer. He suggests calling the local yard in a cooperative spirit and asking them to hold any strawberry signs they might remove.
- There seems to be a good bit of discretion involved. Each NCDOT office can choose how high priority, among its many tasks, it wants to make sign removal, and whether it destroys signs immediately or holds them for a while. Signs that don't impinge on safety and DOT's ability to mow are less likely to be disturbed, even if technically out of compliance, than those that are blatantly "in the way." We've tried to press NCDOT to make it a policy that farm signs are not destroyed immediately.
- Bear in mind that as you move signs off the highway right-of-way, you will want to get permission from the owner of the property your sign will be located on. A few quarts of strawberries can go a long way in these negotiations.
- Be sure that your signs are neat and presentable and that you take them down promptly at the end of the season.
Managing the Peak: Crop Forecasting and Marketing Ideas
By Ervin Lineberger, Kings Mountain, NC, Grower
One of the most challenging aspects of marketing fresh fruit is balancing a variable supply of fruit produced during a season with consumers buying patterns. While growers cannot completely control either of these variables in order to have supply and demand in sync, there are some ways to manipulate both. Bottom-line profit is often affected by how well this is done. Extraordinary profit can be expected if this manipulation or management of supply and demand is accomplished on a high level. In addition to the profit potential, successfully selling a high percentage of fruit produced can be a motivating factor for the grower.
Whether we plan for it or not, growing fruit for a monetary profit is always a process of integrating a production program with marketing activities. Our pre-planning of this process is very important. It is especially critical to have a plan for that period of harvest that we label the peak, when the quantity of fruit ripening is at its highest.
The following suggestions are offered for making a comprehensive plan for managing the peak.
Crop Production: Supply
Management of supply can be based n the following assumptions:
- Fruit production is science-based. The genetic make-up of cultivars assures us that given identical inputs, we can expect identical outputs.
- While we cannot always provide for identical inputs, such as weather, we have learned to predict how plants react to changes in inputs; i.e., warmer temperatures increase rates of growth and maturity, etc.
- Research has produced information that is useful to us. We know, for example, that Earliglo strawberries will ripen relatively early. Arapaho blackberries by nature concentrate ripening in a relatively short period of time. Certain nutrients in fertilizer produce predictable results.
Steps in developing a plan for predicting supply:
- Learn everything you can about the cultivars you grow and cultural practices associated with them.
- Determine when you prefer supply to begin, peak, and end. Fresh-market sales usually are the most profitable when production is spread over a long period of time with uninterrupted production, whereas, a crop grown for processing would best be concentrated in a short period.
- Develop your own formula to produce the supply you want. Variables that you can control should be documented and entered into the formula. These may include but not be limited to: selection of cultivars with various ripening dates, selection of soil types and planting sites, temperature control by any means, vegetative growth control, fruit thinning, etc.
- During the growing season, document growing conditions that occur (especially ones you can't control that will affect supply). These results will be needed to update the formula.
- Combine the following to make a crop forecast approximately two weeks prior to first picking:
- Careful assessment of crop conditions
- Your own undocumented experience
- The most reliable weather predictions available
- The seasonal formula above
- Careful assessment of crop conditions
The forecast should be in 2-3-day increments and predict the harvest potential within each increment.
Manipulation of demand can be based on the following assumptions:
- Consumers tend to develop buying habits from year to year based on their past individual experiences. For example, in the Southern Piedmont of NC, May is considered strawberry month. Sales for strawberries at other times require extra effort by the grower. Most consumers expect a repeat of the past in terms of price, quality, taste, etc. Some resistance should be expected if the grower makes major changes.
- Manipulation of the demand factor is not science-based. Motivating human behavior, in this case purchasing, requires the grower to develop skills quite different from those for production.
- Fresh fruit supply almost always exceeds demand. Therefore, marketing activities usually involve attracting another grower's customers or persuading a consumer to switch choices of food, e.g. to buy strawberries instead of french fries.
- Value and freshness are the two most important incentives for consumer purchases of fruit.
Steps in making a plan for marketing:
Using the crop forecast as a basis, a chart can be constructed to indicate supply for the season in increments. Assuming that major changes in the demand will not take place (such as a new competitor), previous sales patterns can also be used to develop a sales forecast. When combined, these charts will show periods of time when supply exceeds demand, as well as possible times when demand will exceed supply. These are peaks, the main focus of concern and planning.
Some specific activities for peak management include the following:
- Use mailing lists to alert regular customers of abundant supply dates.
- Offer discounts and coupons during peak periods, especially for volume purchases.
- Plan for special activities, such as festivals, during peak periods.
- Arrange with civic clubs located outside service area for fundraiser sales.
- Have "waiting-in-the-wings" customers such as processors, wineries, etc., lined up for large purchases, usually as a last resort.
- Schedule senior-citizen discount days during peak only.
- Divert sales volume from low supply periods through media announcements and advertisements.
- Develop and maintain alliances with other growers for cooperative marketing arrangements.
- Arrange with processors to make products from your fruit that can be sold year-round, i.e., private label wine, frozen fruit, jams, dried products.
- Call-in customers should be advised of times for plentiful supply.
- Allow for an extra ripening day for fruit during the peak (when sales are diverted from wholesale)
- Ask news media to schedule peak, rather than early season, stories. The abundance of fruit and customers is usually a good draw for features.
- Alert gleaners and food banks in advance of the potential peak periods and use on short notice to move excess product.
Some activities not recommended during peak supply include:
1. Pre-season wholesale contracts with other retailers. Usually they will experience the same demand volume; therefore, an agreement to supply may actually create new problems.
2. Price-cutting measures, except for short-term discounts.
Reprinted from the Proceedings of the February, 2002 Southeast Strawberry Expo and North American Berry Conference. Copies of these Proceedings may be ordered from the NC Strawberry Association for $16 each.
Setting Up Your Roadside Market
By Bob Cobbledick, Ontario Farm Fresh Marketing Association. This is an edited version of an article which appeared in the Proceedings of the North American Farmers Direct Marketing Association's recent conference in January, 2001.
One thing I have learned working with roadside marketers is that there are 100 ways to do it right, and no one set of guidelines applies to every market. Often the farm has an existing building that can be converted into a market. This means you have to work within the limitations of support beams and existing inside dimensions. Others may be able to start from scratch, which allows more flexibility in design. It is generally a good idea to keep expenses to a minimum for someone starting out, because the best layout for you will become more apparent to you after a couple of years in the retail business. By then you will have settled on your product line and the constraints of your location. So, the one universal rule is: Never drive the nails all the way in, you never know when you'll want to pull them out to move a wall or build an addition.
1. Look critically at your farm's location. Not every farm is in the right place to do retailing. The more remote you are, the more work it is to draw customers. If you are not well located, you do have options. Consider renting some space at an existing retail business that is well located. Or, investigate renting or putting an option on a smaller parcel of farmland that is on a well-travelled road. If you are considering locating off the farm, try to find a site that will allow you to create the impression of farming, with enough room for some tree fruits, vegetable gardens, or strawberries to convey the image of farm fresh.
2. Zoning is often an issue. In Canada, you are allowed to market what you grow on your own farm. But even then, if the farm is located on a very busy road, growers have been denied building permits or entrance permits for driveways off busy highways. The important thing to remember is work at keeping bureaucrats on your side. When strawberries are in season, find an excuse to visit the local municipal officials and drop some off. When they want support for a food drive or their staff summer picnic, be happy to supply them some sweet corn if they ask, and don't charge them for it. You will find that they will pay you back later in good deeds.
3. Try to position the market so that its back is to the wind and the afternoon sun. This is most critical with open air markets.
4. If you are located where you can service local commuter traffic coming home from work, see if you can build on the side of the road that will allow those customers convenient access to your parking lot without crossing traffic.
5. If your farm is located at the intersection of a major road and a secondary road, try to locate your market so you have an entrance off the major roadway and the exit onto the secondary road. This will reduce congestion at the entrance to your parking lot and give your customers trying to re-enter the traffic flow easier access to several directions on both roads.
6. Be realistic as to your potential as a seasonal vs. a year-round market. If it will be difficult to break even during the winter months, you might be better off taking that time to regroup, get re-energized, and make structural changes.
7. Try to avoid having customer parking in front of your market. The front of a market is your showcase, your chance to create an atmosphere, attract attention, and tantalize customers with outside displays. You're not selling cars, so why feature cars in the front of your market? Capture that potential customer's attention with beautiful landscaping, antique farm equipment, showy flower beds, etc. If there is a direction from which the majority of your traffic will be coming, have your parking on the far side of the market. This allows people to see your operation, slow down, and still have the opportunity to turn into your parking lot.
Watch your building costs. All too often, growers invest too much money in a building and then have to work longer and harder than ever before because of the huge investment. Have a clear goal in mind. If you don't want to market year-round, don't build an expensive building that may force you to be open all year to service the debt. You can do a great job marketing for the spring, summer and fall seasons with a pole barn, or even a tent. (Tents shouldn't need building permits.) What you need is ambience, and that can be created using, flowers, grass, antique farm equipment etc. without a large investment. Starting off economically gives you a chance to try marketing and see if you really like it.
Customer Access & Flow
Make your outside displays of product visible from the road but don't give the customer access to the displays from the outside. Instead, make customers enter the market to access the outside display area. Customers are then given the opportunity to see your indoor retail area, potentially increasing your average sale/customer and reducing the possibility of customer theft.
Traffic Flow inside the market is helped if you:
- have an even number of aisles to reduce the possibility of dead areas within the market.
- lay out your displays and aisles to encourage one-way traffic flow. Design traffic flow to encourage customers to walk by as many of your displays as possible between the entrance and exit (checkout) of the market. Traffic flow should be designed to terminate at the checkout counter. The last thing customers should see is the checkout.
- place important draw items in different quadrants of the market so customers are encouraged to walk more of the retail area to get those popular items. The customer is then more likely to make an impulse purchase, increasing your average sale/customer. An increase of average sale/customer from $5 to $6 increases your gross sales 20%.
- keep aisle widths uncongested. If you plan to use a pallet jack to move bins or display counters, aisles need to be at least six feet wide. If you are going to offer your customers shopping carts, your aisles should ideally be four times as wide as your shopping carts to allow room for a cart to be stopped on both sides of the aisle, and yet still leave enough room for a cart to pass between them with a little extra space.
This is Part I of this article. Part II will be published in the next newsletter, and covers lighting, display, ambience, and more.
Therefore with 2-foot wide carts, aisles should be at least 7 feet wide, 6 feet for the width of the carts plus some extra room because people will not stop their carts touching the display counter.
(e) - if you plan on incorporating a bakery, make it near the end of your traffic flow. You don't want a fresh hot pie or fresh bread to be on the bottom of the shopping cart, being crushed by all the other items. Also let the smell of fresh baked goods tantalize the customer while they shop, so that by the time they reach the bakery area, they have already been subconsciously sold by those wonderful smells.
(3) - Lighting must also be controlled. Because it is important, to focus the customers' attention, on what they are there to buy. There are 2 types of lighting to be concerned with.
(a)- use spotlights rather than florescents in retail areas:
(i) to focus the customer's attention on the product for sale rather than lighting everything equally.
(ii) because incandescent lighting has a better color spectrum which brings out the products' richest colors.
(b) - contol natural light, particularly light coming through windows. Natural light coming through windows on the south or west sides of a market will increase dehydration and cause the fading of colors. Consumers' eyes are drawn to light. Therefore they see the light through the window, rather than the products you hope they will see and buy.
(4) - Controlling inventory and costs are important components of successful marketing. We will not be covering them here, except for one small point that deals with market layout. To improve labor efficiency, try to keep the popular produce section that has to be stocked most frequently, close to the prep area to reduce refilling time. You may even consider making this high traffic aisle a bit wider than the rest to make room for both work carts and shopping carts.
(1) - use dark, green or earth tone display tables. Your eyes are drawn to light, by using light colored display tables, the customer's eye is drawn to the display table rather than the products for sale.
(2) - customers are more impressed by a display that fills their vertical field of vision rather than displays the have great depth, (horizontal field of vision). Therefore, unless you are a market that does a large volume of sales, keep produce display counters no deeper than 2 feet. This will allow you to pile the display higher, filling more of that vertical field, yet controlling the amount of product on display at any one time, thus reducing waste. Besides, consumers don't like to reach much over 2 feet when making a selection from a display counter.
(3) - when making displays, where possible, mix colors, and preferably, put contrasting colors next to each other, (e.g.. red next to green).
(4) - large, light colored price-cards, can dominate the display, distracting the customer from the product itself. If your feature is quality, keep pricing subtle, let the quality sell itself. Consider using chalkboards to feature certain items, with folksy diagrams to entertain and inform the customer about product benefits or price. But because they are black, rather than white, they don't distract the customers' focus from the products on display, but rather they can enhance the shopping experience.
(5) - it is also important to incorporate a sampling area into your display floorplan. There is nothing that will stimulate sales more effectively than allowing customers to sample products. I have seen sales of an item increase by 400%, simply through sampling.
(1) - be careful of refrigerated produce display counters, particularly in the wet section (leafy vegetable section). They tend to be too deep, requiring too much product to make them look full. Refrigerated produce counters also make marketers lazy. The marketer expects too much from them, (in maintaining quality), because they have refrigeration, whereas the real culprit with leafy vegetables is dehydration. Refrigerated produce counters pass a lot of low Relative Humidity air over produce that can dry out leafy vegetables very quickly. It only takes a 5% loss in weight for many produce items to look wilted and unsalable. One alternative to refrigerated counters is misting either by hand or preferably using automatic sprinklers. For a number of produce items, crushed ice is the best way to preserve quality, by reducing both respiration and dehydration. Wet produce, either through misting or by icing displays, have more intense colors, making reds look redder, and produce glistens in the light because of the film of moisture on their surface.
(2) - unless your market's focus is going to be price, make displays using quality products and let the product sell itself.
(1)- the easiest customer you will ever get is the one driving by. So make the outside of your market look as inviting as possible. Incorporate large flower beds of single colors out front near the road, to get the attention of potential customers driving by. Have some well-trimmed grass around part of your market and keep the market's outside paint looking good. Consider having a darker colored market with white trim. Barns often have white trim and this helps convey that rural image.
(2)- give the market a rural ambience both inside and outside to re-enforce the connection between the farm, farm fresh produce and your market. This rural flavor also adds to the customers' enjoyment of their visit to your market.
(3)- if possible, have produce growing in the field beside the market and keep the field weed free and looking beautiful.
(1)- finally and most importantly, when starting a new market, try and find ways or products that will allow you to BE UNIQUE. Ask yourself what is going to make people stop at your operation as opposed to your competition. Is your products higher quality, do you offer better service, cheaper prices, or do you have something no one else offers, something unique that will bring them back again and again. This could be special apple varieties that other markets don't offer, and you can promote their special characteristics. It could be you make 5 different flavors and combinations of raspberry jam. It could be you make your pies from scratch and they have a flakier crust. It could be you have 5 different kinds of apple pie, with different varieties in different fillings or combinations of fruits that only you offer. Or is it your on-farm entertainment that separates you from the others. Whatever it is, remember it is important to be unique!
Bob Cobbledick, Ontario Farm Fresh Marketing Association
324 Lake St. Grimsby ON Canada L3M 1Z4
Tel: 905-945-9057 Fax 905-945-8643
Setting Up Your Roadside Market, Part 2
By Bob Cobbledick, Ontario Farm Fresh Marketing Association. This is an edited version of an article published in the Proceedings of the North American Farmers Direct Marketing Association's January, 2001 conference. The first half of the article appeared in the last issue of this newsletter.
Controlling various aspects of your market will improve its success. If you plan on incorporating a bakery, make it near the end of your traffic flow. You don't want a fresh hot pie or fresh bread to be on the bottom of the shopping cart, being crushed by all the other items. Also let the smell of fresh baked goods tantalize the customer while they shop, so that by the time they reach the bakery area, they have already been subconsciously sold by those wonderful smells.
Control lighting to focus the customers' attention, on what they are there to buy. Use incandescent spotlights rather than fluorescents in retail areas to focus the customer's attention on the product for sale rather than lighting everything equally. In addition, incandescent lighting has a better color spectrum which brings out the products' richest colors.
Control natural light, particularly light coming through windows. Natural light coming through windows on the south or west sides of a market will increase dehydration and cause the fading of colors. Also, because consumers' eyes are drawn to light, they will tend to see the light through the window rather than the products you hope they will see and buy.
Controlling inventory and costs are important components of successful marketing. We will not be covering them here, except for one small point that deals with market layout. To improve labor efficiency, try to keep the popular produce section that has to be stocked most frequently close to the prep area to reduce refilling time. You may even consider making this high traffic aisle a bit wider than the rest to make room for both work carts and shopping carts.
Use dark, green, or earth-tone display tables. Your eyes are drawn to light. If you use light-colored display tables, the customer's eye is drawn to the display table rather than the products for sale.
Emphasize the vertical. Customers are more impressed by a display that fills their vertical field of vision than by displays the have great depth (horizontal field of vision). Therefore, unless you are a market that does a large volume of sales, keep produce display counters no deeper than two feet. This will allow you to pile the display higher, filling more of that vertical field, yet still control the amount of product on display at any one time, thus reducing waste. Besides, consumers don't like to reach much over two feet when making a selection from a display counter.
Mix colors for contrast when making displays. Where possible, put contrasting colors next to each other, (e.g., red next to green).
Keep pricing subtle if emphasizing quality. Large, light-colored price-cards can dominate the display, distracting the customer from the product itself. Unless your market's focus is going to be price, make displays using quality products and let the product sell itself. Consider using chalkboards to feature certain items, with folksy diagrams to entertain and inform the customer about product benefits or price. Because they are black rather than white, chalkboards don't distract the customers' focus from the products on display. Instead, they can enhance the shopping experience.
Incorporate a sampling area into your display floorplan. Nothing will stimulate sales more effectively than allowing customers to sample products. I have seen sales of an item increase by 400 percent, simply through sampling.
Be careful of refrigerated produce display counters, particularly in the wet (leafy vegetable) section. They tend to be too deep, requiring too much product to make them look full. Refrigerated produce counters also make marketers lazy. The marketer expects too much from refrigeration (in maintaining quality), whereas the real culprit with leafy vegetables is dehydration. Refrigerated produce counters pass a lot of air with a low relative humidity air over produce. This can dry out leafy vegetables very quickly. It only takes a 5 percent loss in weight for many produce items to look wilted and unsalable.
One alternative to refrigerated counters is misting, either by hand or, preferably, using automatic sprinklers. For a number of produce items, crushed ice is the best way to preserve quality, reducing both respiration and dehydration. Wet produce, with moisture applied either through misting or icing, has more intense colors, and produce glistens in the light because of the film of moisture on their surface.
The easiest customer you will ever get is the one driving by. So make the outside of your market look as inviting as possible. Incorporate large flower beds of single colors out front near the road to get the attention of potential customers driving by. Have some well-trimmed grass around part of your market and keep the market's outside paint looking good. Consider having a darker colored market with white trim. Barns often have white trim and this helps convey that rural image.
Give the market a rural ambience both inside and outside to reinforce the connection between the farm, farm-fresh produce, and your market. This rural flavor also adds to the customers' enjoyment of their visit to your market.
If possible, have produce growing in the field beside the market and keep the field weed-free and looking beautiful.
Finally and most importantly, when starting a new market, try to find ways or products that will allow you to be unique. Ask yourself: What is going to make people stop at my operation as opposed to my competition? Are your products higher quality, do you offer better service, cheaper prices, or do you have something no one else offers, something unique that will bring them back again and again? This could be special apple varieties that other markets don't offer, and you can promote their special characteristics. It could be you make five different flavors and combinations of raspberry jam. It could be you make your pies from scratch and they have a flakier crust. It could be you have five different kinds of apple pie with different varieties in different fillings or combinations of fruits that only you offer. Or is it your on-farm entertainment that separates you from the others? Whatever it is, remember it is important to be unique!
Contact: Bob Cobbledick, Ontario Farm Fresh Marketing Association, at 324 Lake St. Grimsby ON Canada L3M 1Z4, tel: 905-945-9057; fax 905-945-8643.
Our Experience with Row Cover Hold Down Bags
By Barclay Poling, Extension Small Fruit Specialist, NC Cooperative Ext. Service
It is best to use gravel "hold-downs" to keep the row covers from blowing away and to preserve the cover (Fig. 1). Shoveling soil on the edges of the row cover or using wire hooks will cause more rapid deterioration of the cover than using gravel hold-down bags placed every 5 to 6 feet along the cover edges. Hold-downs can be placed even closer together on very windy fields. The hold-downs are nylon mesh bags filled with enough gravel to weigh about 15 to 17 pounds each (using gravel that is from 1 inch to 2½ inches in diameter). On the farm of Tom Baker in Virginia Beach, they feel that they have best success with #3 rock/gravel (what is used for railroad track ballast). Smaller rock seems to work out through the holes in the mesh bags, resulting in bags getting lighter with use. They are also experimenting with used "crushed" gravel and round (river) gravel, and their thinking is that the smooth river gravel would cut the mesh bags less. But, the jury is still out on that.
Fig. 1. Nylon mesh hold down bags are the recommended way to keep your row covers from "blowing away" and to preserve the cover (photo credit: Donnie Fulks, Belvedere Plantation, Fredricksburg, VA)
Making the bag: The nylon mesh is available in 3,000-foot rolls. To make a hold down, pull off about 36 inches of the nylon to make one bag. Tie a knot at one end of the bag, fill it with the gravel (about two round-point shovels full), and tie off the other end. Instead of making knots, Tom Baker suggest an alternative to tying the bags. He has had better success using black (UV-resistant) zip-strips/cable ties (from an electrical supply house) instead of knots. He says, "They're cheap and easy and "save" several inches of mesh per bag compared to tying knots. For us, cable ties have not deteriorated or come loose. Use a good heavy cable tie (we use 8-inch) and cut the ends with wire cutters after pulling tight." The Bakers have also learned a better way to fill the bags (for one person) by shoveling the gravel into a small bucket (like a horse hoof supplement bucket) that they reinforce with duct tape. Then, just stretch the bag over the bucket and dump in the gravel.
Handle: The stones at the bottom of the bag will flatten-out nicely when dropped on the edge of the row cover (as shown in photo). You can also make a "handle" by evenly dividing the rocks into each end of the hold-down bag. According to Tom Baker, this makes it easy to carry 2 or 3 bags in each hand plus you don't have to bend down as far to pick them up. (Figure 2)
Care in handling: Tom Baker recommends handling the bags gently as treating them roughly will result in cut strands in the mesh with gravel leaking from the resulting holes especially when hauling bags or stacking them at the end of the season.
Bag spacing: Typically, growers will space gravel hold-down bags are placed every 5 to 6 feet along the cover edges, but you may wish to try Tom Baker's approach:
"On our north-south rows in a windy area, we use one bag every 10 feet and put them 8-12 inches "in" from the edge of the row cover. On the ends we put a bag every 5 feet w/ 2 bags at each corner. After a real windy day we'll walk the field and re-position the few bags that work loose. Putting a bag every 5 or 6 feet would be great --if-- someone else carries them in/out of the field. Knocking on wood (my head), I'll say we've had very little problem with row covers getting loose with a bag every 10 feet, but too many is better than too few!"
Care of fabric: Tobacco bed hooks, old tires, and chunks of wood can be used in place of hold downs, but these are not recommended as highly as the hold down rock bags, which do not cut or tear the row cover fabric.
The following sell the mesh for making hold-down bags:
Berry Hill Irrigation, 3744 Hwy 58, Buffalo Junction, VA 24529
Eastfield Farms, P.O. Box 275, Mathews, VA 23109, 804-725-3948
Reddick Fumigants, Inc., 3002 West Main St., Williamston, NC 27892
Fertility and Irrigation