Tag Archives: Fall garden

August is the Time to Plant for the Fall and Winter Garden in the Washington DC Metro Area

mustard

mustard

August is the time for harvesting and enjoying the summer’s bounty in the vegetable garden while thinking ahead to a winter’s garden. Even though it is hot and humid, planting carrots, green onions (scallions), and cole crops such as cauliflower, broccoli, broccoli raab, Brussels sprouts, cabbage, and collards will give great yields in cold months. Later or by September, also consider planting spinach, Swiss chard, radish, turnip, and Asian or hardy greens such as mustard, tatsoi, mache, and kale. You still have time to plant garlic: that’s in October.

To determine when to plant look at the “days to maturity” on the seed packet. Count backwards from the average first frost date (Halloween in Northern Virginia) to determine when to plant. But the difference between fall and spring planting is the “Short Day” factor, which may not be addressed on the seed packet. If you are going to plant seed, you have to add 2 weeks to the numbers on the seed packet to allow for the cooler night temperatures and the shorter day lengths.  For example, to sow spinach seeds add the 7 to 10 days for germination, 35 days to reach maturation, and 14 days for the Short Day factor for a total of 56 to 59 days. Therefore, the latest one can sow spinach seeds is the beginning of September. The length of time would be shorter if nursery transplants were used instead of seed because they have a head start.

mache

mache

Also, find out the best temperature range for seed germination (start indoors versus outdoors), keep the seeds moist during dry times in the summer, and get to know each crop’s tolerance for cold (soil and air) to know if you should provide additional warmth with row covers.

Virginia Cooperative Extension

Vegetable Planting Guide and Recommended Dates #426-331

University of Maryland Extension

Planting Dates for Vegetable Crops in Maryland #HG16

Vegetable Planting Calendar for Central Maryland #GE-007

Southern Exposure Seed Exchange

Southern Exposure Seed Exchange is a Virginia-based seed company that also has very useful local information:

Fall and Winter Quick Reference

Fall and Winter Gardening Guide

Fall Vegetable Gardening

This past July, popular seed companies announced that it was time to start the fall vegetable garden but I dismissed it as it was high summer and I was rolling in red tomatoes and yellow peppers. Now, as the tomato plants begin to yellow and the peppers turn red, I am focusing my attention on cool season veggies in hopes of reliving the greens I enjoyed this past spring. I did not plan for it though, it caught me by surprised. August is a time for harvesting and processing the summer bounty while at the same time planting another round of seeds for the fall/winter/spring edibles, depending on what you plant and if you can extend the season with covers. I was fortunate enough to have seed left over from the spring and planted pak choi, sugar snap peas, lettuce, scallions, spinach, and carrots both in the garden bed and in containers.

spinach seedlings

spinach seedlings in a basket

Last weekend I attended a 90-minute presentation called “Fall Vegetable Gardening,” where Libby Good, a Virginia Cooperative Extension Master Gardener, expanded the concept of fall vegetable gardening to include planting crops to harvest before frost or that can overwinter, planting cover crops to add nitrogen, extending the season with cold frames or row covers, garden clean up, and overall getting ready for the next year. Libby explained that planting in the fall has advantages: the soil is workable, the air temperatures can be cooler with less direct sun, the moisture levels can be higher, and there can be fewer insects and weeds. “Most fall veggies don’t rely on pollinators and are high in nutrition,” she said.

sugar snap pea seedling

sugar snap pea seedling

Libby also explained that if you are starting seed or buying transplants you have to first determine your frost date, which Libby says is around Halloween in the Northern Virginia area. Then you have to work backwards to determine when to plant the seed or transplant. But the difference between fall and spring planting is the “Short Day” factor, which usually is not addressed on a seed packet. If you are going to plant seed, you have to add 2 weeks to the numbers on the seed packet to allow for the cooler night temperatures and the shorter day lengths. According to her handout, if you want to sow spinach seeds for a fall harvest (i.e., before first frost), you have to add the 7 to 10 days for germination, 35 days to reach maturation, and 14 days for the Short Day factor for a total of 56 to 59 days. Therefore, the latest you can sow seeds is the beginning of September. The length of time would be shorter if you bought transplants from a nursery.

pak choi seedlings

pak choi seedlings

Another factor to keep in mind is the plant’s tolerance for cold temperatures, for example, beets, cauliflower, chard, Chinese cabbage, endive, kohlrabi, lettuce, mustard, peas, and rutabagas can survive light frosts. Broccoli, broccoli raab, Brussels sprouts, cabbages, collards, kale, radishes, spinach, and turnips can survive heavy frosts. Chicories, garlic, kale, leeks, multiplier onions, spinach, and shallots can stay in the ground over winter.

carrots in a fabric bag

carrots in a fabric bag

You can extend the season, which means to be able to harvest after frost, by protecting the plants from low temperatures with row covers, cold frames, hoop houses, and greenhouses. Libby has been gardening for many years and uses both row covers and cold frames to extend her harvest. She passed around her own row cover, made out of a synthetic fabric that allows light and water through and provides several degrees of protection. She also showed photos of her cold frames which she made with discarded windows. By growing greens in a cold frame she was able to harvest lettuce in February.

“Fall Vegetable Gardening” was free, courtesy of the Virginia Cooperative Extension and Master Gardeners of Northern Virginia, and will be offered again on Thursday, September 4, at Fairlington Community Center, 7:00 to 8:30 pm; and Saturday, September 20, 10:30 to noon at the Barrett Branch Library. Call (703) 228-6414 or e-mail mgarlalex@gmail.com to register in advance. http://www.mgnv.org