A Man for all Seasons
Eliot Coleman discusses the details of year-round gardening
By HELEN LAMMERS-HELPS
It was his “disinclination to give over his markets to the Californians every fall” that first piqued organic grower Eliot Coleman’s interest in four-season vegetable production at his Harbourside, Maine farm. While traditionally growing vegetables in the winter has meant using heated greenhouses, Coleman, a true innovator, sought a different approach. He wanted to see how much he could produce without supplemental heat.
Simplicity, low external inputs, and high-quality outputs were the guiding criteria for his year-round gardening system. “Our goal was to find the lowest tech and most economical way to extend fresh-vegetable harvest through the winter months,” he says. Coleman, who has been growing vegetables year-round on a commercial scale since 1995, has developed a fine-tuned growing system through his attention to detail.
Last year he produced $120,000 worth of vegetables from 1.5 acres, with only a quarter of an acre under cover, using very little supplemental heat.
Farming on the “back side of the calendar,” as he calls it, has many advantages. It means he can hold his markets, keep his crew employed, and it provides a more balanced year-round income, he says.
Growing vegetables year-round at Coleman’s Maine farm is no small feat. Located two-thirds of the way up the Maine coast on the 44th parallel, temperatures can dip as low as -29 degrees C. Using standard, plastic-covered, gothic style hoop houses allows Coleman to mimic growing conditions 500 miles south of his farm. Adding a second layer of protection, a floating row cover 30 cm above the soil, simulates growing conditions a thousand miles south of his farm, he says. Coleman calls his unheated greenhouses “cold houses,” as opposed to “hot houses.”
“Using the double layer of protection lengthens the growing season on both ends, basically for free, no heat required,” he explains. The only cost is the cost of the greenhouse and the row cover material.
Another key to the system is growing vegetables that do well in the cold instead of heat-loving plants such as tomatoes. These vegetables include spinach, Mesclun (a mix of baby salad greens), carrots, mâche, watercress, and potatoes. Many cold-tolerant vegetables can easily survive temperatures down to -12 degrees C or lower as long as they are not exposed to the additional stresses of outdoor conditions, he explains. The double coverage also increases the relative humidity in the protected area, which offers additional protection against freezing damage. Any type of lightweight floating row cover that allows light, air and moisture to pass through is suitable as the inner layer of material in the cold houses, he says.
Coleman maximizes the use of his greenhouses by moving them to where they’re needed. For example, he starts spinach in the greenhouse and once it’s safe from frost, about the third week in March, he can move the greenhouse to another location and use it to start another crop like carrots. By the end of April, the carrots no longer need protection and then he can start another crop like zucchini. This allows him to double the use of his capital investment in the greenhouses, he says. “We became involved with greenhouses because of our interest in growing winter crops and then wondered how to best use them for the rest of the year,” he says.
Planting at the right time for your conditions and environment is also crucial, he says. “For example, the trick with winter-harvest crops is to get the seeds in the ground in September, not November, so the crop has a chance to grow and put out new leaves,” he explains. “I think of August-September as the second spring.” Successive seedings also ensure a continual harvest. Read the full, original article at Small Farm Canada. Eliot Coleman’s The Winter Harvest Handbook, The New Organic Grower, and Four Season Harvest are available now, in addition to his new workshop DVD, Year-Round Vegetable Production with Eliot Coleman.