Autumn has traditionally been the time to put the garden to bed. As a wildlife gardener, I look at my gardens as living ecosystems. My gardens provide shelter, food, and water for the local wildlife as well as provide me with food, lovely flowers, and interesting foliage.  So putting the garden to bed means creating a place that can support wildlife during the winter and improve the garden’s health and yield in spring and summer.Â
Probably the most important thing you can do this autumn is add a deep layer of fallen leaves to the garden. If you use oak leaves, chop them up a bit because they take longer to break down and you will get more matting than aerated mulch. If you have a shortage of easy-to-access fallen leaves, you can always pick up the filled leaf bags from your friends and neighbors.
Leaf mulch adds organic matter to your garden soil, protects the roots of your perennial plants, and keeps the soil from heaving if your winters include times of freezing and thawing. In winter, leaf mulch also provides shelter for spiders, ladybugs, toads and salamanders. These beneficial creatures feed on harmful insect creating a more balanced ecosystem. This means you will have less insect pests eating your plants during the growing season.
Native bees, like bumblebees, hibernate under leaf litter. If you can support hibernating bees in your garden then they will be out pollinating that much earlier come spring.  Leaf mulch also attracts birds in the spring as they search for insects to feed their fledglings or themselves after a long flight north.
Some butterflies hibernate in the north, though in different forms. Your leaf litter provides an environment in which they can survive the winter. Coral Hairstreak butterflies pass the winter as eggs. Viceroy and Red Spotted Purple butterflies hibernate as larvae. Gray Hairstreak and some swallowtails hibernate as pupae. Mourning Cloak, Question Mark, and Comma butterflies hibernate as adults.Â
So in the winter, your garden can be a wildlife haven if you let fallen leaves lie.  But as it true for us northern gardeners, we will not see the fruit of our labor until spring.