Did you know that our spring garden cleanup practices have a profound impact, either positively or negatively, on pollinators and, by extension, the birds who live in our gardens? This article will discuss ways to gently tidy with the goal of supporting pollinators, fireflies and birds.
Rather than raking leaves and sending them to the dump, leave them on your garden beds. It’s okay to rake them from areas like the driveway or lawn but keep them in the garden and leave them whole, not mulched.
Many, if not most, native butterfly and moth species (and other beneficial insects such as lacewings and ladybugs) overwinter in dead leaves. A recent study showed that removing leaves from one’s yard reduced butterfly and moth species richness by 40% and abundance by 45%. Mulching leaves showed a similar decline (Ferlauto, Burghardt, 2025).
Fewer butterflies and moths also mean fewer birds since most bird species rely exclusively on caterpillars to raise their young (Tallamy 2024). Fewer lacewings and ladybugs mean more aphid problems.
There is no “safe” time to remove leaves since overwintering insects emerge at various times throughout the growing season. A case in point is the life cycle of fireflies. Female fireflies lay their eggs in decomposing leaves and the larvae and pupae remain there or underground until they emerge as adults. This process can take a few months or up to 3 years depending on the species (Stefan, 2024).
Most spring blooming bulbs and native woodland plants, including ferns, easily poke their way up through dead leaves but it’s okay to open a bit of space for them to emerge.
The leaves are also an excellent mulch and help retain soil moisture and block weeds from emerging. The leaves will gradually break down and feed the soil while sustaining soil microorganisms.
Dead perennial stems may be cut back to 8 to 24 inches and left standing to provide nesting sites for native bees including carpenter bees, yellow-faced bees and leaf-cutter bees. The stem cuttings can be left in the garden for birds to use as nesting material. Orioles in particular like to use milkweed stems to build their nests. The dead stems of warm season grasses such as Little Bluestem (Schizachyrium scoparium) are also popular nesting material and can be left standing until June when new growth appears.
By following these suggestions you will be saving yourself a lot of work but, more importantly, you’ll be welcoming more caterpillars, birds, butterflies, moths, bees and fireflies to your garden.
References
Ferlauto, M., Burghardt, K.T. (2025). Removing autumn leaves from residential yards reduces the spring emergence of overwintering insects. Science of The Total Environment vol. 970 (178821). https://www.sciencedirect.com/science/article/pii/S0048969725004565
Stefan, A. (2024). Firefly. The Canadian Encyclopedia https://www.thecanadianencyclopedia.ca/en/article/firefly
Tallamy, D. W. (2024). The chickadee’s guide to gardening. The Upstate Chapter of The NC Native Plant Society. https://scnps.org/wp-content/uploads/2024/04/SCNPS_Tallamy_Chickadee_0219.pdf
Written by Carolyn Schmidt, Tri-County Master Gardener
