August is the time for harvesting the summer’s bounty in the vegetable garden while thinking ahead to a winter’s garden. Even though it is hot and humid, you have to plan now to have even more edibles in the fall and winter. These edibles prefer cool temperatures. Often these plants are not bothered by as much disease and pests as in the summer plus you as a gardener are not bothered by heat, humidity, and mosquitoes.
Consider planting carrots, green onions (scallions), cauliflower, broccoli, broccoli raab, Brussels sprouts, cabbage, and collards will give great yields in cold months. Later in 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. Remember what happened this spring and get a jump on purchasing your seed; check out this list of seed companies.
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.
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.
Even though it feels like summer, plan ahead and order your seed now for more edibles that prefer cool temperatures. Below are handouts for more information from Virginia and Maryland extension offices as well as a local seed company.
Virginia Cooperative Extension
University of Maryland Extension
Southern Exposure Seed Exchange