As summer's crops begin to flag in their production and look more and more ragged, the urge within many gardeners to tidy up and start anew is strong. Luckily, this is a good time to heed that urge.
UGA's Vegetable Planting Chart, which includes names of many vegetable varieties that are known to produce well in Georgia, shows planting dates for fall garden vegetables as well as for the spring garden. The planting dates are for "middle Georgia," some distance south of Atlanta, which means the dates will need to be adjusted for the cooler weather in Cobb County by bringing the fall planting dates deeper into the summer by two or three weeks.
South of Atlanta, the first frost is fairly reliably in mid-November or later, but it is closer to October's end in Cobb. In order for the plants to reach maturity in a timely manner (before next spring), we need to get our fall vegetables started sooner. For example, the chart shows fall planting dates for lettuce as falling between Aug. 1 and Sept. 1. Adjusting those dates for our earlier first frost brings us to mid-August as being near the end of the best time to start lettuces from seed in the garden. This doesn't mean that lettuce started from seed in September will be a total bust, only that it might not reach its full size by the first frost.
The good news is that we usually get plenty of warm weather after the first frost, before winter really sets in, so vegetables will continue to mature past the frost date. However, growth will slow substantially, and any plants that are too young might not survive the first frost without protection.
Auburn University Cooperative Extension, in its publication Basics of Fall Vegetable Gardening, recommends similar planting dates for residents of Alabama. The publication also offers general advice about planning and planting for a successful fall garden and for protecting tender plants from a hard freeze. Click on the link (above) to read the full text (pdf format).