Some ideas from an expert

Rosaly Bass, owner of New Hampshire’s first certified organic garden, has been farming organically at Rosaly’s Garden in Peterborough, N.H., for 36 years.

Rosaly Bass, owner of New Hampshire’s second largest and oldest certified organic farm, Rosaly’s Garden, says, “We think of every possible problem that could arise and then every possible strategy to avoid it naturally.” Among the strategies that Bass, along with Matt Gifford, her farm manager, and Betsy Marshall, her greenhouse, herb and flower manager, use to control pests and diseases on the Peterborough farm’s 17 cultivated acres are crop rotation, physical barriers and trap crops.

When the old canister vacuum cleaner that powers this seeder is turned off, one tiny seed of all those dumped onto a piece of Plexiglas falls into each countersunk hole over each cell of a 288-plug tray.

Bass grew up in the Berkshires in the tradition of organic agriculture. Her mother grew all the fruits and vegetables for a family of seven and her father kept milking shorthorns. Her mother believed that growing food organically was good for the health of the body and of the environment, and that chemical pesticides and fertilizers were not—even before J.I. Rodale (who popularized the term “organic” to mean growing without pesticides), Adele Davis and Rachel Carson. “I don’t know where my mother got her strong feelings about growing organically,” says Bass, “but they definitely were there and we knew about them.”

In 1973, Bass began gardening at her husband’s farm in Peterborough, N.H. Each year her garden grew larger, as did the number of customers eager to buy at the farmstand or to pick their own berries, herbs and flowers. Thirty-six years later, Bass continues to farm organically, and serves as a resource to other farmers and gardeners.

Beginning with the soil

Test, test, test—every section, every year, says Bass. Over the years, the silty loam of Rosaly’s Garden has been enriched and nourished regularly and is now high in organic matter. Soil samples from at least 25 sections are tested annually. After analyzing test results, University of New Hampshire Extension’s George Hamilton determines what nutrients should be added based on the soil’s current composition and its intended use in the coming growing year. Hamilton cautions against guessing, using liming as an example. In an area where adding lime annually is often routine, soil analyses indicate Rosaly’s Garden is an exception. Because the holding capacity of the soil on her farm is so high, liming needs to be done only once every five or six years.

Planted in black plastic, eggplant serves as a trap crop for potato beetles, detering them from infesting the nearby tomato plants.

Cover crops are a routine part of nutrient management, as well as soil erosion prevention. Annual ryegrass is seeded between sections and is a part of the approximately $800 per acre per year cost of soil amendments.

Outwitting pests

Number one among strategies for avoiding pest problems at Rosaly’s Garden is crop rotation. “It is also good to be very diversified,” she says. Because it may take pests up to three weeks to find their favorite crop, moving the crop annually is one of the best strategies for preventing insect damage. In the time it takes the insects to search for their target crop, the plants have a chance to grow stronger and more resistant to damage.

Other strategies include physical barriers such as floating row covers. Firmly anchored by rocks and soil, floating row covers are put in place over crops where pest problems are anticipated. Black plastic helps deter potato beetles. The first generation of potato beetles can’t fly, and because the black plastic is slippery, they can’t crawl up the raised rows to reach the plants. Another barrier to pests is the 60-foot-wide grass landing strip for small aircraft. It can take pests up to three weeks to find their way across the strip’s tall grass.

Trap crops serve to outwit some pests. Cucumber beetles adore zucchini, so zucchini is planted to attract the beetles and keep them from the other 3.5 acres of cucurbits. Once the beetles have infested the zucchini trap crop, the zucchini is either sprayed to eliminate the beetles or it becomes a sacrificial crop. Eggplant serves as a trap crop for tomatoes, protecting against potato beetles. Flea beetles, which survive New Hampshire winters, love arugula (and any other mustard variety found in mesclun) even more than cole crops, so arugula is planted as a trap crop near members of the Brassicaceae family.

Lettuce is seeded and re-seeded throughout the season. Lettuce and mesclun (consisting of arugula, parsley, mustard, tatsoi and six varieties of lettuce) are second to tomatoes in Rosaly’s Garden as the most important cash crop.

A single strand of electric fence surrounds the strawberries. “Usually, deer don’t eat strawberries,” says Gifford, “but they like ours.” To help deter deer, an electric fence is baited with peanut butter on aluminum foil. A shock to the nose quickly persuades deer to keep away from the fenced area.

Greenhouse, Herb and Flower Manager Betsy Marshall.

Beneficial insects and nematodes are also used. When all else fails, and always as a last resort, natural sprays certified for use by the Organic Materials Research Institute (OMRI) are applied.

Other pest and disease prevention strategies

Although one of the six 100-foot greenhouses at Rosaly’s Garden is double-layered, solar heated and maintains soil temperature at 45 degrees Fahrenheit or above year-round, it is operated only three seasons. “We don’t want to operate any greenhouse four seasons because of the possibility of year-round pest pressure,” says Gifford. Other greenhouses and all three-season tunnels, used for growing transplants in spring and for spinach, kale and beets in fall, have their sides rolled up in winter.

Organic potting soil is used for starting seeds in a ground-level, sealed, temperature and humidity-controlled growing room in Bass’ home. This strategy allows greenhouses to remain unused for a longer period of the year, reducing the possibility of pest pressure and also saving energy.

Seed selection is another part of the farm’s disease prevention strategy. “Know your seed source,” says Gifford, citing as an example the farm’s loss of garlic to blue mold one season. The seed garlic had come from a new supplier. Most of the farm’s seeds are organic and are purchased from established sources, such as Johnny’s Selected Seeds. When organic seed is not available, untreated seed is used.

For children, there’s a scavenger hunt for plastic animals in the herb gardens.

New this year is an attempt to use wind to blow away potential plant disease. Because the prevailing wind is east to west, tomatoes have been planted in east-west rows.

Weed control

Black plastic works well to control weeds in Rosaly’s Garden. Drip lines laid beneath the plastic also heat the soil and, in some instances, delay insect damage. The 5.5 mil black plastic is put in place with machines, and tape helps hold it in place. Between rows, annual ryegrass discourages weed growth.

Landscape fabric is used to cover some newly seeded varieties such as dill, cilantro, green beans and carrots to speed their germination. Because the covered crops germinate before the weeds, they are larger and easier to see when weeding.

Seeds are started in a temperature and humidity-controlled growing room.

Ready-picked, pick-your-own and more

Sixty kinds of vegetables, herbs and flowers can be ordered by mail in February for spring pickup. Order entries include information on container size (pot or six-pack), unit price, name and variety of plant, growing time and seed source. Early orders help the farm grow the varieties and number of plants customers want.

Of the several hundred varieties of fruits, vegetables, berries, herbs and flowers grown at Rosaly’s Garden by 17 employees, 90 percent are sold at the farm. Tomatoes, lettuce and salad mix are the largest crops, but the acre of pick-your-own flowers attracts the most attention. The open-air farmstand, which stocks in-season offerings as well as prepared foods, is open daily from 9 a.m. to 6 p.m., mid-May through Columbus Day. Strawberries, raspberries and blueberries, as well as flowers and herbs, are available for customers to pick. The 10 percent of the farm’s offerings not sold on the farm are sold to grocery stores, a natural food store, a cooking school and several private schools.

Shady picnic tables overlooking the gardens and a view of Mount Monadnock welcome visitors to Rosaly’s Garden. For the next generation of organic gardeners and consumers, there’s also a scavenger hunt for plastic animals hidden throughout the medicinal and herb gardens.

“Know your seed source,” says Farm Manager Matt Gifford. One crop of garlic from a new seed source came infected with blue mold.

Some advice for new farmers

Bass says, “Being certified organic is definitely worth it.” She also strongly encourages beginning farmers to try not to hire workers, which brings both the need to share profits and the risk of labor complications, she says. Lastly, a farmstand takes lots of labor and hence is a big expense.

Kathleen Hatt is a freelance writer and editor, and a frequent contributor to Growing and other agricultural publications. She lives in Henniker, N.H.