If you’re not quite ready to store your gardening tools, fall is a great time to get your soil ready for next year’s planting, said Rosie Lerner, Purdue Extension consumer horticulture specialist (retired).
“Removing this year’s plant debris is a good, general sanitation practice,” said Lerner. “Plant refuse makes a great place for insects and diseases to overwinter.” She suggested turning that refuse into valuable compost. A properly constructed compost pile should create temperatures high enough to destroy insects, diseases, and most weed seeds. “Once the compost has decomposed (hopefully by spring), it can be worked into the soil to add organic matter and some nutrients,” she said.
“Tilling and incorporating organic matter during fall avoids the rush of garden activities and often waterlogged soil in spring,” said Lerner. “Adding organic matter will help improve soil drainage and water-holding capacity, and loosen up heavy soils.” Homeowners can incorporate materials such as dry tree leaves, grass clippings, and livestock manure (none from pets).
“Summer mulch should be well decomposed by spring, if plowed under in fall,” said Lerner. “Work these materials into the top 5-7 inches of soil with a rototiller or shovel.” However, she suggested that garden sites that are prone to erosion by wind or water over winter should not be turned until spring.
“Fall is a great time to collect soil samples for testing in order to keep current on your garden’s nutrient status,” said Lerner. “Testing in fall allows plenty of time to receive your results and act on recommendations.” There are a number of private certified laboratories that offer soil-testing services.
However, Lerner cautioned that the test results and recommendations will only be as good as the soil samples that you send in. “Make sure your samples are representative of your garden,” said Lerner. “Small cores of soil 6-8 inches deep should be taken from several spots throughout the garden and then mixed together.”
The Purdue Extension publication, “Collecting Soil Samples for Testing,” explains this process more thoroughly. Search for the publication at https://edustore.purdue.edu/. Soil testing labs have websites that explain their protocols for submitting a sample, and their contact information.
Finally, cover crops are a good option for improving soil health and decreasing the chances of erosion in home gardens. A Purdue Extension publication covers the particulars of cover crops, including species, seeding rates, seeding dates, and termination options. Note that most cover crops should have been sown much earlier, so this may be an idea for next year. For further information, search for “Cover Crops in the Home Garden” at the above website.