University of Illinois Extension

Fall is for Planting

Fall is a key season for next year's garden, said a University of Illinois Extension horticulture educator.

"The nursery industry has been successful in promoting the planting of trees and shrubs with their campaign called 'Fall is for Planting,'" said Greg Stack. "While you may not want to plant trees and shrubs, this slogan can also work for those of you who may want to plant salad greens and root crops for a fall and early winter harvest."

If we can rely on "what's normal," fall will bring some cooler, moister weather and what better time to plant things that like it cool?


"Think about lettuce, spinach, radishes, kale, carrots, Asian greens, beets and maybe a few cool season flowers like calendula and violas," he recommended. "All of these crops are easy from seed and many times garden centers still have seed racks in place with seed packets at a reduced price.

"If you plan ahead you can reap the bounty of weeks and maybe months of fresh, tender greens, sweet carrots and beets. Even in Illinois, it is possible to grow fresh vegetables late into the fall and, with some light cover, early winter. Start with checking the seed packet for the "days to maturity" of the crop you want to grow. Add about 14 days to the number and then subtract that sum from the average first frost date for your area. This gives you a ball park seed starting date."

For example, if you want to grow spinach that matures in 40 days, sow seed 54 days or 8 weeks before the frost date.

Crops such as spinach and lettuce really don't like warm soils and tend not to germinate well. To get around this consider a few gardening tricks. Start the seed indoors or in containers placed in the shade and then transplant the seedlings to the garden. Sow seeds in the shade of taller plants like corn or tomatoes.

"Or, take a page from the Old Farmer's Almanac," he said. "It suggests that you moisten the soil and then lay down a bale of straw. A week later the soil under the straw will be about 10 degrees cooler. To extend your harvest well past frost, and maybe until the first snowflakes fly, consider some type of season extender.

"Construct a "box" around your salad greens with straw bales and lay some old storm windows across the top. This is about as basic a cold frame as you can get and will protect the crop from the cold and allow you to harvest well past the time many gardens have fallen to the frost."

The same thing can be done by bending thin, plastic water pipe into hoops over the row and then pulling clear plastic sheeting over the hoops, he added. The plastic can be lifted during the sunny parts of the day, closed at night for protection and all the while the crops under these "hoop houses" produce some great fall greens and root crops.

"If you don't want to involve yourself with building all of these protection devices plant crops such as broccoli, spinach, chard, Asian greens, kale, collards and Brussels sprouts," Stack said. "These crops are naturally tolerant of frosts and will last well into the season until a very hard frost occurs."

For root crops like carrot, beets, turnips, and parsnips mulch over the row with a thick cover of straw. Straw will protect the crop and prevent the soil from freezing. When you want to harvest, pull back the straw, dig your crop, recover with the straw and take your sweet root crops into the kitchen to enjoy. It would not be uncommon to harvest root crops even when there is a cover of snow on top of the straw.

"While the 2012 gardening season was filled with challenges, give fall gardening a try," he said. "You may find that with a little effort in picking and sowing the right crops you can still end the season on a productive note and have home grown salad greens for Thanksgiving."