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Home  > Question of the Week

Question of the Week

Permalink How can I grow strawberries using plasticulture?

Answer: The term plasticulture refers to the practice of using plastic materials in agricultural applications, most often as a plastic plant or soil covering. Organic and conventional growers in California and Florida, where most of the nation's strawberries are produced, tend to favor plasticulture growing systems. They grow plants as annuals, transplanting strawberry crowns in the late summer or early fall. Production starts in the late winter and continues through the summer and into late fall, depending on the area and the varieties grown. Since methyl bromide is not allowed in organic production, crop rotation, green manure crops and compost are critical to control soil-borne diseases and pests.

Two types of raised beds are used in plasticulture systems. Narrow beds have two rows of plants with one drip line running between them. The distance between beds averages 40 inches. Drip tape is buried at a depth of about 2.5 inches. Wide beds usually have four rows of plants and two drip lines, with 64 inches between beds. Spacing between plants in both types of bed averages 12 to 14 inches.

Plastic mulch is used in both narrow and wide beds and can vary from a single strip of plastic laid between the plants to full bed coverage, where holes must be punched for the plant to develop. Some conventional growers in California use clear plastic, which warms the bed faster, stimulating early-season growth. These growers use fumigation to control most weeds. Black plastic is used in organic production, primarily for weed control. Since the black plastic prevents the sun's rays from penetrating, the beds remain cool, resulting in slower initial growth of the plants and reduced irrigation frequency compared to clear plastic mulch. There is a plastic mulch on the market that selectively permits soil-warming radiation to penetrate while eliminating the light that promotes weed growth. This type of plastic is preferred by growers in the Southeast.

Raised beds provide good drainage. Since they make the flowers and fruit easier to see and reach, raised beds also help growers to forecast yields, while making harvesting easier and faster. Some growers dig deep furrows between the beds so that harvesters do not have to stoop so low to search for fruit. In cold climates, plants in raised beds may be prone to freeze damage. Still, raised beds usually out-produce flat beds. Due to increased aeration and protection from splashing soil particles, plants in plastic-mulched raised beds have less disease.

Machinery is available to shape the bed, lay out the irrigation line, and cover the bed with plastic mulch all in a single pass. Sources of bed-shapers and transplanters are listed in the ATTRA publication Season Extension Techniques for Market Gardeners. Or check the following web pages:,

Recent research indicates that any variety that normally does well in a specific region will do well when grown using plasticulture in that region. However, some of the cultivars that come from the California and Florida systems perform best at a 12- to 14-inch spacing, while many northern cultivars do best at an 8- to 10-inch spacing.

By now, growers and researchers in many states have adapted and validated at least parts of the production model described above. Growers should check with their state Extension Fruit Specialist to see if specific plasticulture guidelines are available for their area. Otherwise, a complimentary copy of Nourse Farms' Success with Plasticulture can be obtained by calling Nourse Farms at 413-665-2658.

Plasticulture is not without its serious critics. The plastic has to come from somewhere, and it has to be discarded at the end of the one- to three-year production cycle. Clearly, critics say, this is not an environmentally sustainable system. And, says Cornell University fruit researcher Marvin Pritts, PhD, if you consider all the environmental costs to society, plasticulture is also not economically sustainable in the long run. Pritts also points out that even more plastic—in the form of row covers, tunnels, hoop houses, etc.—is needed to make the system work in cold climates.

USDA researchers have shown that fields mulched with plastic cause four times more water runoff than fields mulched with organic materials. Due to this high rate of runoff, fields mulched with plastic suffer up to 15 times more soil erosion than fields mulched with organic matter. Planting grasses or other types of vegetation alongside drainage ditches can reduce the rate of erosion and provide habitat for beneficial insects.

Yet, even organic growers—especially those in California, where plasticulture has reigned the longest—are buying into the plasticulture production model. Why? The answer is weeds. Strawberries are notoriously prone to weed encroachment with resultant loss of productivity. Plasticulture provides good to excellent weed control without herbicides. The USDA National Organic Program (NOP) states that plastic or other synthetic mulches are allowed in organic production, provided that they are removed from the field at the end of the growing or harvest season.

For more information on growing strawberries, see the ATTRA publication Strawberries: Organic Production at This publication provides an overview of organic strawberry production methods. It also covers integrated pest management and weed control techniques that can reduce pesticide use in strawberry production. Included are discussions of weeds, pests, diseases, greenhouse production, plasticulture, fertility, economics, and marketing. Lists are provided of further resources, both electronic and in print.

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Permalink What can you tell me about keeping bees on my farm?

Answer: Working with bees requires a gentle touch and calm disposition. It also requires a basic understanding of the honey bees' behavior during the various seasons and during handling and moving.

It is usually wise to start small, learn efficient management techniques, and expand the beekeeping operation as time, experience, and finances permit. Initial outlay can reach $200 per hive, and other equipment, such as a smoker, veil, gloves, feeding equipment, honey extractor, etc., will add to the expense.

It is best to learn beekeeping skills from an experienced beekeeper. You'll learn basic skills required for opening hives, removing frames, identifying queens, and recognizing the difference between honey and pollen in a cell. You can find beekeepers by joining a local bee club or state organization. Bee Culture magazine provides a list of contacts in each state.

Beekeeping can be labor-intensive during certain times of the year. It is not a seasonal enterprise—it requires year-round management. Beginning beekeepers needs to consider their available labor limitations and keep the enterprise at an easily managed size.

Other things beginning and experienced beekeepers may need to consider include:

Location of hives. Hives should not be located near homes or areas used for recreation. Hives need to be near nectar and pollen sources and fresh water; protected from predators, vandals, and adverse weather conditions; and accessible throughout the year.

Processing honey and other bee products. Follow state and federal regulations for processing, labeling, and handling food products.

Marketing honey and other bee products. Consider different types of products and marketing strategies. Will you market to consumers at farmers markets or on-farm, to retailers, to a honey cooperative, or to honey packers?

Disease and pests control. Mites, beetles and disease are things to be aware of and know how to treat.

Anyone interested in keeping bees for pollinating plants or for producing additional income from bee products should first investigate all available sources of information. County Cooperative Extension offices are a good source of information on beekeeping, as are entomologists and apiculturists at your local land-grant university. State apicultural inspectors, usually with the U.S. Department of Agriculture, are another good source of information. These sources should be able to provide contact information to local beekeepers. Hobbyists are often very willing to discuss their management techniques, problems, and solutions. These contacts will indicate successful techniques that have been used in a specific climatic or geographic area.

For more information see ATTRA publication, Beekeeping/ Apiculture at This publication is intended as a guide for anyone interested in beginning or expanding a beekeeping enterprise. Whether the bees are kept as pollinators for crops or for the income from their products, producers need to be aware of their state's apiary laws concerning inspection, registration, and permits, as well as labeling and marketing standards.

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Permalink What resources are available for beginning farmers?

Answer: There are a tremendous number of resources to help beginning farmers and ranchers with planning, securing land, and making a success of their operations. As the premier source of sustainable agriculture information, ATTRA offers important resources for beginning farmers and ranchers and people who work with them. Some of our resources for beginning farmers are listed below.

For information on business planning and farm profit, see the ATTRA publication Planning for Profit, at This introductory publication discusses some basic questions that will help you plan for profitability. Understanding your financial capability, your costs of production, and the potential profitability of alternative ways to market products are examined. A list of additional resources is included for further study.

Another resource that may be helpful for beginning farmers is the ATTRA publication Evaluating a Farming Enterprise, available at There is a growing movement within the United States to get back to the land—to start developing hands-on, land-based careers. The faces of new farmers vary widely, from young college graduates to others who are starting a second career or simply retiring into farming. Those in second careers often own land and need help developing an enterprise that works with their property and goals. Those who have recently graduated still want to make a go of farming but often have the added challenge of not owning land. Determining what to grow and how to sell it are the first steps in starting a farm-based business. This publication will help the reader take these important first steps.

The ATTRA publication Financing Your Farm: Guidance for Beginning Farmers, available at, lays out several financing options available to beginning farmers to start a farm and to illuminate the step-by-step process of applying for a loan. Small- and medium-scale sustainable farmers and those new to the world of finance are the target audience for this publication. The intention is to help these readers consider a range of options for raising capital and reducing expenses involved in starting a farm, with a bank or government loan as just one tool, albeit an important one, in a whole toolkit of creative possibilities.

If you are a beginning farmer (that is, you have not been farming for more than 10 years but have worked at a farm for three years or more), there are Farm Service Agency (FSA) loans for beginning farmers. For more information, see

The ATTRA publication Building Sustainable Farms, Ranches and Communities, available at,
is written for anyone seeking help from federal programs to foster innovative enterprises in agriculture and forestry in the United States. Specifically, the guide addresses program resources in community development, sustainable land management, and value-added and diversified agriculture and forestry. Thus, it can help farmers, entrepreneurs, community developers, conservationists, and many other individuals, as well as private and public organizations, both for-profit and not-for-profit.

For a list of additional funding opportunities for farmers, see

To find non-ATTRA resources available for beginning farmers, see

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Permalink How do I store post-harvest produce until bringing it to market?

Answer: You have spent months working in the fields, and you now have a bountiful harvest of beautiful fruits and vegetables. You want to ensure that your customers will also enjoy this healthy harvest. How can you best maintain the quality and safety of your produce as it travels from the field to the table? How can produce be stored so that it does not need to be sold immediately? High-quality, disease-free produce with a good shelf life is a result of sound production practices, proper handling during harvest, and appropriate postharvest handling and storage.

Production practices have a tremendous effect on the quality of fruits and vegetables at harvest and on postharvest quality and shelf life. To start, it is well-known that some cultivars ship better and have a longer shelf life than others. In addition, environmental factors such as soil type, temperature, frost, and rainy weather at harvest can have an adverse effect on storage life and quality. For example, carrots grown on muck soils do not hold up as well in storage as carrots grown on lighter, upland soils. Lettuce harvested during a period of rain does not ship well and product losses are increased.

Management practices can also affect postharvest quality. Produce that has been stressed by too much or too little water, high rates of nitrogen, or mechanical injury (scrapes, bruises, abrasions) is particularly susceptible to postharvest diseases. Mold and decay on winter squash, caused by the fungus Rhizoctonia, result from the fruits lying on the ground and can be alleviated by using mulch. Broccoli heads are susceptible to postharvest rot caused by the bacteria Erwinia if nitrogen is applied as foliar feed—a grower should feed the soil, not the leaves. Beets and radishes are susceptible to soil-borne diseases when the soil temperature reaches 80º F; symptoms are black spots on these root crops.

Food safety also begins in the field and should be of special concern, since a number of outbreaks of food-borne illnesses have been traced to contamination of produce in the field. Common-sense prevention measures include:

• Don't apply raw dairy or chicken manure or slurries to a field where a vegetable crop such as leafy lettuce is growing.
• Don't apply manure to an area immediately adjacent to a field nearing harvest maturity.
• Don't forget to clean equipment that has been used to apply manure to one field before moving it to another field in production.
• Don't irrigate with water from a farm pond used by livestock.
• Don't harvest fruit from the orchard floor for human consumption as whole fruit or nonpasteurized juices, especially if manure has been spread or if animals allowed to graze.
• Don't accumulate harvested product in areas where birds roost.

A grower should constantly evaluate water used for irrigation and compost all animal manures before applying them to fields. There are many good sources of information on growing conditions and production practices that promote postharvest quality. Consult ATTRA publications, textbooks, Extension publications, and trade journals. You can also become involved with grower organizations to learn more.

Harvest Handling
Quality cannot be improved after harvest; it can only be maintained. Therefore, it is important to harvest fruits, vegetables, and flowers at the proper stage and size and at peak quality. Immature or over-mature produce may not last as long in storage as that picked at proper maturity. Cooperative Extension Service publications are an excellent source of information on harvest maturity indicators for vegetables and fruits.

Harvest should be completed during the coolest time of the day, which is usually in the early morning, and produce should be kept shaded in the field. Handle produce gently. Crops destined for storage should be as free as possible from skin breaks, bruises, spots, rots, decay, and other deterioration. Bruises and other mechanical damage not only affect appearance, but also provide entrance to decay organisms.

Postharvest rots are more prevalent in fruits and vegetables that are bruised or otherwise damaged. Mechanical damage also increases moisture loss. The rate of moisture loss may be increased by as much as 400 percent by a single bad bruise on an apple, and skinned potatoes may lose three to four times as much weight as non-skinned potatoes. Damage can be prevented by training harvest labor to handle the crop gently, harvesting at proper maturity, harvesting dry whenever possible, handling each fruit or vegetable no more than necessary (field pack if possible), installing padding inside bulk bins, and avoiding over- or under-packing of containers.

Postharvest and Storage Considerations
Packaging should be designed to prevent physical damage to produce and be easy to handle.

Temperature is the single most important factor in maintaining quality after harvest. Refrigerated storage retards the following elements of deterioration in perishable crops:

• Aging due to ripening, softening, and textural and color changes
• Undesirable metabolic changes and respiratory heat production
• Moisture loss and the wilting that results
• Spoilage due to invasion by bacteria, fungi, and yeasts
• Undesirable growth, such as sprouting of potatoes

One of the most important functions of refrigeration is to control the crop's respiration rate. Respiration generates heat as sugars, fats, and proteins in the cells of the crop are oxidized. The loss of these stored food reserves through respiration means decreased food value, loss of flavor, loss of salable weight, and more rapid deterioration. The respiration rate of a product strongly determines its transit and postharvest life. The higher the storage temperature, the higher the respiration rate will be.

For refrigeration to be effective in postponing deterioration, it is important that the temperature in cold storage rooms be kept as constant as possible. Exposure to alternating cold and warm temperatures may result in moisture accumulation on the surface of produce (sweating), which may hasten decay. Storage rooms should be well-insulated and adequately refrigerated and should allow for air circulation to prevent temperature variation. Be sure that thermometers, thermostats, and manual temperature controls are of high quality, and check them periodically for accuracy.

For more information, see theATTRA publication, Post Harvest Handling of Fruits and Vegetables, available at This publication covers postharvest practices suitable for small-scale operations and points out the importance of production and harvesting techniques for improving quality and storability. Various methods for cooling fresh produce are discussed, and resources are listed for further information, equipment, and supplies.

Additionally, the Western Sustainable Agriculture Research and Education project and ATTRA partnered to produce a Post-Harvest Handling and Food Safety Guide, available at

Finally, a publication from North Carolina State University, titled Postharvest Handling and Cooling of Fresh Fruits, Vegetables, and Flowers for Small Farms. Part II: Cooling, may be helpful to have on hand in your washing facility. It is available at

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Permalink What should I know before starting a CSA?

The USDA defines Community Supported Agriculture (CSA) as a community of individuals who pledge support to a farm operation so that the farmland becomes, either legally or spiritually, the community's farm, with the growers and consumers providing mutual support and sharing the risks and benefits of food production. Members or shareholders of the farm or garden pledge in advance to cover the anticipated costs of the farm operation and farmer's salary. In return, they receive shares in the farm's bounty throughout the growing season, as well as satisfaction gained from reconnecting to the land. Members also share in risks, including poor harvest due to unfavorable weather or pests.

The CSA concept was brought to the United States by Jan VanderTuin of Switzerland in 1984. Projects in Europe date to the 1960s, when women's neighborhood groups approached farmers to develop direct, cooperative relationships between producers and consumers. By 1986, two CSA projects in the United States had delivered harvest shares from Robyn Van En's Indian Line Farm in Massachusetts and the Temple/Wilton Community Farm in New Hampshire.

Over time, two distinct types of community supported agriculture have emerged:
the shareholder CSA and the subscription CSA.

Subscription CSA (farmer-driven). In this approach, the farmer organizes the CSA and makes most of the management decisions. Farm work is not required of subscribers. A permutation is the farmer cooperative, where two or more farmers organize to produce a variety of products for the CSA basket. Subscription CSAs now constitute more than 75 percent of all CSAs.

Shareholder CSA (consumer-driven). This type of CSA typically features an existing "core group" that organizes subscribers and hires the farmer. The core group may be a not-for-profit organization and land may be purchased, leased, or rented. Most key decisions are made by core group personnel.

Vegetable production (most CSAs focus on vegetables) is a highly complex, financially risky career, demanding great creativity and professionalism. To initiate a farming operation with the CSA structure may not be the wisest choice for a beginner. The operation, from the very start, will face the dual challenges of mastering complex production and post-harvest handling techniques, while simultaneously managing and servicing the needs of an unusually large customer base. Existing vegetable operations that add CSA as market diversification strategy appear to have a high likelihood of success.

For more information, see ATTRA publication Community Supported Agriculture, available at This publication reports on the history of CSAs in the U.S. and discusses the various models that have emerged. It also addresses recent trends in the CSA movement and demographic information about the distribution of CSA farms in the U.S. In addition, the publication profiles several CSAs and presents a survey of recent research.

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