In days gone by, late autumn meant the raking and burning of fallen leaves. That’s right, burning. There was a time, when setting a mound of leaves and garden debris on fire was allowed, and in some smaller towns, even today, the smell of burning leaves—quite distinct from the smell of a barbecue or even a fireplace—infuses the cool autumn air.
But is this compunction for cleaning up leaves, dead plant stalks and flower heads a product of some misguided notion of man’s dominion over nature? If we look to nature’s gardens—forests and grasslands—as an example of good gardening practices, you won’t see anyone out there with a rake and garden waste bag. The closest thing to a fall cleanup is a wildfire caused by a lightening strike, a hungry herd of ruminants, or the slow, inevitable process of plants becoming humus.
Perhaps there is wisdom in nature. But some gardening experts will insist that a fall cleanup is absolutely necessary for the prevention of disease and maintaining order. Arlene Hazzan-Green and Marc Green, owners of The Backyard Urban Farm Company, are two seasoned gardeners who say there are pros and cons to leaving a garden to its own devices. For example, they agree that it’s lovely to feed the birds, but leaving dead and decomposing plant matter on the ground could offer shelter for unwanted pests. So, if you aren’t inclined to completely tidy your yard before winter, conduct a selective cleanup; one that won’t invite pests and diseases. For example, pull out annuals and cut back perennials that show signs of pest infestation. And, of course, come spring, introduce helpful insects such as ladybugs and praying mantises to take care of some of the bad guys.
Here are some reasons why you might want to retire your rake and pruners for the season.
Your garden can generate a ready-made winter mulch
Autumn leaves are more than pretty. Fallen leaves lie on the ground, forming a protective, moisture-retaining layer for the grass, clover or whatever groundcover lies beneath. As the sun warms and melts the snow, water flows through any debris left on the ground, pulling nourishment from the decomposing matter, down to the roots, feeding the soil. Dead leaves require fungus to break down, warn the Greens, whereas other organic matter will be consumed by bacteria. The problem? These same funguses may find their way to your beloved ornamentals. Furthermore, leaving dead and decomposing plant matter on the ground is providing insect pests with a cosy place to bed down for the winter. Eggs, pupae and even adult insects can burrow down under all that brown stuff and find safe haven, only to emerge in the spring very hungry and in the mood for love.
If you're not in the mood to rake, small leaves left on the ground will allow air and water to pass through, but big leaves need to be shredded—try running a mower over them a few times to create a nice leafy mulch.
Your garden can provide food for birds and animals
Spiky dead flower heads provide seeds for wintering birds—goldfinches especially love thistle and echinacea—and wizened wild grapes give pretty, rosy house finches a much-needed blast of sugar. Squirrels will make a winter snack of dried morning glory seeds—getting wildly drunk in the process—and if there’s even one serviceberry left on the tree, you just know a robin who has stayed north too long, will enjoy the berry’s energy and vitamin C.