Green Thumb – Fall Garden Clean-Up for Pollinators & Wildlife

Posted: September 25, 2023

As the gardening season winds down, many of us will begin cleaning up our landscapes for the winter. While cutting back dead plants and raking leaves can make for a clean-looking yard, it may not be the best thing for pollinators and other wildlife that inhabit our landscapes.

While monarch butterflies and some species of birds will migrate south for the winter, most of our pollinators and other wildlife will stick around. Depending on the species, this can be as an egg, larva, pupa, or adult. During that time most insects will enter diapause, when they stop developing due to unfavorable conditions.

What should I do with my leaves?

Leaves on lawns are commonly raked up and then bagged to be taken away or burned. Instead of getting rid of your leaves, consider leaving at least some of them where they are. Left in garden beds or out of the way areas, leaves will provide habitat for overwintering insects like swallowtails, luna moths, and bumble bee queens.

One common concern with fallen leaves is that they will smother and kill turfgrass. This is certainly true if you have a thick layer of leaves on your lawn. However, if only 10-20% of your lawn is covered in leaves, they can be left where they are. If more of your yard is covered, you can rake the leaves from your lawn into garden beds or other areas of your property where they can serve as a mulch, and break down over time.

Alternatively, leaves in your lawn can be mowed several times and mulched into your turf. This will help return nutrients back into the soil and build organic matter.

Cleaning up perennial plants

Instead of cutting down dead plant material this fall, wait to remove it until spring and embrace its beauty this winter. Leaving flower stalks, dead/dried leaves, and grasses to stand can add dimension and visual interest to a landscape.

This dead plant material can also be habitat for pollinators and other beneficial insects. Some of these insects may lay their eggs on them. Many butterflies will pupate and spend the winter on these plants as well. By leaving this plant material in the landscape, we can preserve these insects for next year.

Leaving flower stalks in your landscape can also benefit birds. The seed heads of plants like black-eyed Susan, sedum, purple coneflower, Joe-Pye weed, and marigold can be an important food source for seed-eating birds, like finches, during the winter. The insects that overwinter on these plants will provide food for their baby birds in the spring. In addition, this dead plant material will catch leaves which can provide extra insulation for the plants.

If you feel like you need to cut back your plant material, keep it in your landscape instead of getting rid of it. If you remove flower stalks, bundle them up and put them in an out-of-the-way area. Some of our native bee species, like small carpenter, mason, and leaf-cutter bees may utilize these hollow stems as nesting habitat.

One exception to waiting to clean up flower beds and gardens is if you’ve had issues with diseases or insect pests. Often these organisms will overwinter on plant debris. Controlling weeds now may lead to fewer weed problems in the spring. Winter annual weeds, like common chickweed, will germinate in the fall and resume growth in the spring.

Instead of being in a hurry to clean-up, channel your inner procrastinator and enjoy the changing seasons. The things you “need to” clean-up will still be there come spring.

Ken Johnson is a Horticulture Educator serving Calhoun, Cass, Greene, Morgan and Scott counties. He is one of the authors of the “Good Growing blog” at The Green Thumb page is coordinated by DeKalb County Master Gardener Janice Weber.