Overwintering Crops

In the April issue of Growing for Market, we published an excerpt from Eliot Coleman’s new book, The Winter Harvest Handbook, in which he promotes low tunnels as an inexpensive alternative to high tunnels/hoophouses. Coleman says that high tunnels make sense for the crops that you have to tend to or harvest during the winter, such as greens, leeks and carrots. But for those that will be planted in fall and then left alone until spring, low tunnels are much more economical -- 5 percent of the cost of the same area under high tunnel.

Eliot Coleman's new book, The Winter Harvest Handbook, proves that he continues to experiment and innovate - and that he is meeting with considerable success, with gross revenue of $80,000 per acre on his coastal Maine farm.

The season is drawing to a close, but there’s still work to be done. You can plant certain vegetable and flower seeds now to overwinter for an extra-early harvest next year. Garlic needs to be planted in fall. And you can extend the season of your current crops by being ready for the changing weather ahead.

With the inexpensive protection of a caterpillar tunnel or Quick Hoops™ low tunnel, many crops can be harvested throughout the winter. Initial crop selection is critical. The best crops for winter harvest include hardy greens such as arugula, mache, mustard, and spinach; and root crops such as beets, carrots, leeks, and radishes. Within those categories, look for varieties with special cold tolerance, denoted with the snowflake symbol.

Predictably, since a new word is easy to co-opt, “regenerative” has quickly become the darling of the large industrial agriculture companies who are now able to mouth ecological platitudes, formerly associated with organic farming principles, but without any intention of following them. We are seeing well-honed, corporate co-opting skills used very effectively by professionals.

The suspicious old organic hippie in me finds the new “re-generative” movement to be a devious attempt to displace organic in the public mind with a more manipulatable word, easily controlled and redefined by the agricultural industry. I can understand many of the large mid-western long-time chemical farmers not liking the word “organic” and thus a new word being useful to communicate with them. All well and good. Use the word “regenerative” to lure them in to being better farmers.

As high tunnel production has gained popularity, an increasing number of growers are moving on to what could be considered the next level of complexity — movable high tunnels. Eliot Coleman has been promoting movable hoophouses for more than 15 years, but they have been slow to catch on, possibly because they required more engineering and building skills than most people possess.

Eliot Coleman keeps on inventing. A trip to his Maine farm in June 2009 captured a few new ideas.

Greens are quick, easy crops that can be grown year-round to meet the constant demand for them. Greens can become one of the foundation crops on which a market farm depends; with proper scheduling, they will bring in steady income without a lot of fuss.

Demand for local food doesn't suddenly disappear at the first frost. Committed locavores want to buy local food year-round, providing new opportunities for fresh market growers who would like to increase annual revenue and cash flow during the winter.

In the southern half of the United States, fall is the best time to plant hardy annuals that will bloom next spring. Some of the best hardy annuals used as cut flowers include  agrostemma, bachelor buttons, bupleurum, larkspur, and nigella. Any other flowers that normally self-seed in your garden are also good candidates for fall seeding. Some will germinate in fall, grow into small plants, and then go dormant. Others won’t germinate this year, but will sit in the soil until the chilling requirement is fulfilled and the weather warms. Larkspur is a good example of a cut flower that is much stronger and taller when direct seeded in fall.

Farmers are always talking about the weather, moreso this year than usual. The mild winter, lack of snow cover, and record-breaking March temperatures across most of the U.S. have generated a lot of talk and worry that insect pressure will be worse than usual this season.

Entomologists say that’s not necessarily true. Insect pressure will be different, for sure, but it may not be worse and might even be less for some crops. A lot depends on the overwintering biology of specific pests, populations last year, and the weather going forward this spring and summer.

Once crops have been harvested, it's time to clean up the remains. Field sanitation consists of plowing down, composting, or otherwise removing plant debris, and mowing adjacent areas. Flowering plants can be left to provide seed for birds, but otherwise plants should be removed from the soil surface to prevent overwintering of pests and diseases.

Usually when garlic is ready to be harvested and dealt with, the farming year is in full swing, and bodies and brains are tired a lot of the time. We have made ourselves a checklist to help things go more smoothly, and make sure no important step gets forgotten. This also helps new crew know what they are supposed to be doing when and if they get confused.

Sweet corn presents challenges for organic farmers. Some of these can be easily overcome; others warrant careful
consideration. There’s no denying that sweet corn takes up a lot of space, so if you are really short of land, you may decide to forego corn. On the other hand, corn doesn’t take a lot of work, so if you have space, but are short of help, corn is a good choice. The rewards are probably obvious: devoted, satisfied customers! Organically grown hybrid varieties (such as Luscious, Sugar Pearl, Brocade) are available, which helps USDA Organic certified commercial growers.

Carol Deppe, in her delightful book The Tao of Vegetable Gardening: Cultivating Tomatoes, Greens, Peas, Beans, Squash, Joy and Serenity, (Chelsea Green, 2015) introduces us to her new way of growing cooking greens: Eat-All Greens. Carol grows these by broadcasting seed of one of her carefully chosen greens crops in a small patch. When it reaches 12” tall, she cuts the top 9” off for cooking, leaving the tough-stemmed lower part, perhaps to grow for a second cut, or to be returned to the soil. It’s best to sow each kind in a separate patch, even if you want mixed greens later, as different crops grow at different rates. I wanted to try this idea in Virginia, where the climate is fairly different from the Pacific Northwest where Carol lives.