Q. I heard I should not cut down my perennials as it benefits wildlife. Is it true?
A. Leaving your garden alone in fall is a great idea. As cold weather comes, wildlife is looking for places to call home for the winter. Lots of insects, frogs and other creatures are out in gardens overwintering in the leaf litter and twigs, and even in the top layer of soil.
What happens if you "clean up" your garden? You might be tossing out a black swallowtail chrysalis or a mantis egg case. Also, fall cleanup leaves a barren landscape for birds and other creatures when food supplies and vegetative cover are becoming sparse.
Think of fallen leaves and withered stalks not as waste but as an organic windfall for your garden and potential wildlife habitat. Lady beetles, most butterflies and other insects will bed down among the stalks during the cold season. When autumn approaches, stop removing spent flowers and allow them to go to seed. Birds will dine on the seeds of sunflowers, coneflowers, grasses and other plants. Remove only diseased plant parts and leave the rest standing. Disposal of diseased plants should be done in a refuse bag and not composted.
Leaves are an often overlooked resource that can be beneficial as mulch. Shred the leaves before using as mulch to increase the surface area. Also, shredded leaves decompose more quickly. This allows for the decaying microorganisms to do their job, act as a natural weed suppressant and conserves water year round.
Shredded leaves can be used as mulch in garden beds as well as under trees and shrubs. Don't volcano the mulch under the trees or shrubs. The mulch should look more like a bagel/doughnut to keep the mulch away from the tree bark.
Another way to enhance habitat in the fall is to create a few brush piles. They will be snug winter quarters for lizards, frogs, toads as well as bumblebees and other native bees. The leaves and other dead vegetation are like a "down comforter" for winter wildlife. Start a brush pile with a layer of loosely stacked or crisscrossed branches and add stalks and leaves on top.
If you have an overabundance of leaves and clippings in your yard, compost. In fact, autumn is a great time to make compost since there is a good mix of leaves, some spent plants and grass clippings. This means you will have a combination of carbon (leaves and other brown material) and nitrogen (grass clippings and other green material such as kitchen scraps), which produce compost quickly. Keep the pile moist and turn it often, and you will have compost to use in your garden come spring. Or just leave it alone to decompose slowly.
Rethinking your fall cleanup is a win-win situation. You will protect your plants and enrich your soil safely while laying out a winter welcome mat for wildlife. It involves a lot less work, enabling you to look forward to autumn gardening with anticipation rather than dread.
-- Terri Passolt
• Provided by Master Gardeners through the Master Gardener Answer Desk, Friendship Park Conservatory, Des Plaines, and University of Illinois Extension, North Cook Branch Office, Arlington Heights. Call (847) 298-3502 Monday, Wednesday and Saturday or (847) 201-4176, ext. 14, on Fridays. Visit web.extension.illinois.edu/mg.