I’m not a hot weather lover. Sure, I want some summer days in the 80s to help the tomatoes and squash ripen. But while those veggies are reveling in the hot sun in July and August, I’m out in the garden, weeding and watering, and thinking wistfully of those nice, cool fall days ahead. I think the autumn months are the pleasantest time of the year to be outside, so I always look forward to the fall gardening season. Lots of delicious crops are suitable for a late harvest, even in areas like Vermont with a short growing season. Fall crops are also a great choice for school gardens, as they can be harvested (and in some cases planted) after students have returned from their summer break.
Late season gardening does take a little advance planning, however. For many of the crops to be ready to pick in early to mid-fall (or even late fall and winter, depending on your climate), they’ll need to be planted in mid to late summer in order to have time to mature before the weather turns too cold.
One of my favorite veggies for fall eating is kale. In order to have an ample harvest of both baby greens for salads and full-size leaves for soups and sautés, I plant some seeds in cell packs in mid to late July. When the seedlings are several inches tall, I set them out in the garden, covering the bed with lightweight row cover fabric stretched over hoops. Covering plants is an easy way to keep away pests like flea beetles and caterpillars, although kale seems to be less enticing to these critters than many other cabbage family members. I’ll make another sowing of kale a few weeks later, in mid-August. Then toward the end of the month and again in mid-September, I’ll sow seeds directly in the ground, to be harvested as “baby” leaves. If I’m really organized, I’ll even sow some seeds inside a cold frame in late September. This way, I’ll have a good chance of being able to serve home-grown kale at Thanksgiving dinner – maybe even Christmas!
Many other greens make great fall crops. Spinach delights in cooler temperatures and isn’t tempted to bolt (flower and go to seed) in the shortening days of fall. Swiss chard, bok choy, Asian greens like mizuna and tat soi, arugula, and mache are all great candidates for late season harvests. Root crops such as carrots, beets, radishes, and turnips are other possibilities, along with that weird and wonderful member of the cabbage family called kohlrabi. Cabbage, broccoli, and Brussel’s sprouts can all be grown for fall harvest, but because they take a relatively long time to reach maturity, in many parts of the country at this point they would need to be set out as started plants purchased from a garden store.
So how do you know when to start these various plants so they’ll be ready for harvest in the fall? You just need to do a little arithmetic. First, find out the average date of the first hard fall frost in your area (most of the crops suggested tolerate temperatures at least down to 28°F). Next, look for the days to maturity listed on the seed packet. Take this number and add in 10-14 days as a fall factor, which takes into account the slower growth that happens as a result of the shorter, cooler days of fall. Add to this the number of days of the harvest period. Then count back this number of days from the frost date and —ta-da!—you have your planting date.
Actually, what this really gives you is a good “ball park” idea of when to plant. Because the weather and actual frost date varies from season to season, starting some seeds earlier and some seeds later than the calculated planting date will give you the greatest likelihood of a long and abundant harvest season. And if you plan to give plants protection, in a cold frame for example, you can often add another 2-4 weeks to you growing season. Keep in mind that cold tolerance can also vary within a particular crop, depending on the variety you choose. For example, choosing lettuce varieties bred for fall harvests will set the stage for late season success.
Enjoy the fun —and wonderful weather—that fall gardening affords. A little planning now will let you and your students enjoy the bounty of a school garden for months to come!