Gardening Tips for the Midwest Region for September (all regions at link)
Prune those trees that are susceptible to disease if pruned in the spring, such as maple, birch, oak, and mountain ash.
This is a great time to plant new trees and shrubs because the new roots will have plenty of time to become established before the spring.
Fall is the best time to start lawn grasses from seed. Till the soil before sowing and provide several light waterings each week.
Dig the herbs from your garden and plant them in pots to bring indoors for the winter; such herbs include rosemary, parsley, chives, and thyme.
Begin moving houseplants inside.
Perennials can be divided and replanted.
Watch for frost forecasts. Harvest tomatoes before the first killing frost. Ripen indoors away from sunlight.
Harvest Brussels sprouts and parsnips once they’ve been exposed to frost.
If you want to prolong your fall crops, sow radish, lettuce, spinach, and other greens in cold frames.
Be sure to bury or throw away any fallen fruit to help keep away any unwanted pests from your yard.
Compost garden debris and kitchen scraps.
Take root cuttings from annuals, such as begonias, geraniums, and impatiens; plant them in a container and keep them in a sunny place indoors.
Save the seeds from your favorite self-pollinating flowers. Dry the seeds and store them in sealed containers for the winter.
Improve your garden soil by adding manure, compost, and leaves to provide it with more organic matter.
Aerate your lawn if the soil is compacted. Have your soil tested to see if you need lawn fertilizer.