With tomatoes, peppers and melons now hitting their late summer stride, it’s easy to forget that autumn can be as abundant as spring and summer. But those who seize the opportunity for a second season will find the planning worthwhile as they munch on garden-fresh produce as Halloween approaches.
The steps to a bountiful fall garden are simple: Choose crops suited to fall growing conditions. Ensure your site has organically enriched soil and adequate water. And start now.
Replace spring-planted crops with new plantings that mature in fall. Seeds and transplants will take off quickly in warm summer soil. When deciding what to plant for fall, gardeners throughout most of the country should focus on greens and root vegetables, says John Navazio, a plant-breeding and seed specialist at Washington State University Extension and senior scientist for the Organic Seed Alliance in Port Townsend, Washington.
In nearly any part of the country, you can grow these cool-weather crops into autumn: leafy greens such as lettuces, spinach, arugula, chard and mâche; root veggies such as beets, carrots, turnips, radishes and rutabagas; brassicas including broccoli, cabbage, cauliflower, collards, kale and Chinese cabbage; and peas. In many regions, some of these fall crops will survive the winter to produce a second harvest in spring.
If you garden where winters are mild, you can grow all of those crops plus heat-lovers. “Here, we set out tomato transplants in late August,” says David Pitre, owner of Tecolote Farm, an organic farm near Austin, Texas. Pitre plants okra, eggplant, peppers, winter squash, cucumbers and potatoes in August and September for winter harvest. In warm climates, wait to plant cool-weather crops until after temperatures cool—in late September or after.
Fall is also prime garden season in the Pacific Northwest, where abundant rain and cool (but not frigid) temperatures are ideal for growing brassicas, root crops and leafy greens planted in mid- to late summer. The hardiest of these crops often hang on well into winter if given protection such as row covers.
To determine starting dates for your fall garden plants, check the “days to maturity” in the seed catalog or on the seed packet. Add an extra week or two to factor in fall’s shorter day lengths, which delay plant maturity. Then to determine your ideal planting date, count backward, subtracting the days to maturity from your average first fall frost date (find yours at the National Climatic Data Center).
Start broccoli and cabbage seeds indoors (summer soil may be too hot for good germination), then transplant them to the garden about four weeks later, when temperatures are cooler and seedlings are large enough to compete against weeds. Direct-seed greens, carrots, beets and other root crops into prepared beds.
Because you’re likely planting fall crops in soil that has already fed a spring planting, replenish beds with organic fertilizer and/or compost before planting. If autumn and winter weather in your area is wetter than in summer and you have clay-heavy soil, you might also want to use soil to build planting beds higher than the surrounding ground to help improve drainage. And, if your soil requires amendments to adjust its pH (you can determine this with a soil test, available at garden centers), add a dose of them before your fall planting.
Seeds and transplants take off quickly in warm soil with adequate water. To help retain soil moisture, surround seedlings with a thick layer of mulch. Finely shredded leaves or straw will keep soil moist while slowly contributing organic matter to the soil as they decompose.
Keep plants growing strong as temperatures drop by giving them a midseason nutrient boost. You can make a foliar fertilizer by mixing 1 tablespoon each of fish emulsion, seaweed and molasses in a gallon of water, then spraying it on leaves, says Carol Ann Sayle, co-owner of Boggy Creek Farm in Austin, Texas. Elizabeth Keen of Indian Line Farm simply feeds plants compost. “We’ve found the best time to apply compost to the soil around the plant’s base it is when it’s a ‘teenager’—about four weeks after transplanting.”
A final tip for your most bountiful fall garden: Harvest early and often. Frequent cutting stimulates continual new growth and gives you plenty of chances to enjoy the fruits of your labor.
Hardy Fall Crop Varieties
After you’ve decided which crops to grow for fall harvest, zero in on specific varieties. “There are big differences in cold hardiness among varieties,” Navazio says. “Some are better able to photosynthesize at cooler temperatures.”
For the past several years, the Organic Seed Alliance has been conducting trials of as many as 170 varieties of 11 different fall crops for their quality and performance in fall and winter. Among them, kale, radicchio and Swiss chard have been tested extensively and confirmed cold-hardy to 14 degrees with no protection. Read below for growing tips for a variety of cool-weather crops, as well as the vegetable varieties that stood out for the Alliance and market gardeners.
Arugula. Tuck pinches of arugula into rows of shallots and onions; they’ll grow quickly and smother any weeds that might overtake your slower growers. Suggested varieties: Astro, Sputnik
Beet. To keep soil from forming a crust that will inhibit seedlings from emerging, cover newly planted rows of beets with boards or cloth, and remove it as soon as the little seedlings peek through. Suggested varieties: Chioggia Guardmark, Red Ace, Shiraz, Touchstone Gold
Broccoli. Opt for varieties that produce plenty of side shoots, rather than a single large head. Suggested varieties: Diplomat, Marathon, Packman
Carrot. Consider storage ability when choosing carrots for your fall garden. Suggested varieties: Bolero
Spinach. For a continued harvest, snip off individual leaves as you need them, keeping the central rosette intact. Suggested varieties: Olympia, Space, Tarpy
Mâche. Mâche, or corn salad, continues to grow when lettuces go dormant in winter. Suggested varieties: Golden Corn Salad
Kale. All varieties of kale have superior flavor when temperatures drop into the 20s or below. Suggested varieties: Black Tuscan, Winterbor, Red Russian, White Russian
Lettuce. Several varieties will hang on into December and, with the protection of heavy mulch or a cold frame, will often return with renewed vigor in early spring. Suggested varieties: Rouge d’Hiver, Marvel of Four Seasons, Winter Density
Collards. Large and architecturally interesting, collards make excellent edible landscaping plants. Suggested varieties: Champion, Flash
Radicchio. Grown in cool weather, versatile radicchios have a mild, spicy flavor. If some outer leaves are damaged by the cold, simply strip them off. Suggested varieties: Variegata di Luisa Tardiva, Variegata di Castelfranco, Rossa di Verona, Grumolo Rossa di Verona
Swiss Chard. Green varieties tend to be most cold-hardy, followed by gold, then pink, magenta and red varieties. Suggested varieties: Fordhook Giant