Before You Clean Up Plant Debris, Consider the Benefits of a Messy Yard
Melanie Radzicki McManus
Fall finds most homeowners with clippers in hand, busy cutting down plant remains and clearing debris from their yards in preparation for winter. Conventional garden wisdom says this helps control pests and disease, and, more importantly, keeps yards looking nice.
But now some experts say leaving your planting beds intact over the winter—not being so tidy—is beneficial for your garden, because an amazing array of insects and arachnids use dead plant stems, leaf piles and other summer debris as winter homes. Some of these creatures will later keep destructive insects under control; other may help pollinate plants.
So what critters are actually trying to bed down in your yard? Ladybugs and lacewings like to nest in the dry, sheltered crowns of native grasses, says Cheryl Long, a senior editor at Organic Gardening, while pollinating bees prefer hollow plant stems. Butterflies and moths often spend the winter in chrysalides on the ground, adds Craig Tufts, chief naturalist at the National Wildlife Federation. And baby spiders hide at the base of old stems, using them as supports for their webs come spring, when new plant growth is not sturdy enough. There are also creatures that nestle under leaves and other dead vegetation to insulate themselves from winter’s chill. “It gets kind of cold without that ‘down comforter,’ ” says Tufts, “which also provides the insects with protection from predators.”
Lending some urgency to the situation is the recent discovery by Andrew Williams, an honorary fellow in the University of Wisconsin-Madison’s entomology department. Williams discovered an average of 15 diverse animal species over wintering in the stems of various prairie plants, with one particular plant harboring an amazing 31 different species of insects. Most people garden with nonnative plants, Williams says, which cuts down on the diversity of insects likely to be present in plant stems during the winter months. Nevertheless, he says gardeners should definitely consider postponing their annual cleanups until spring.
Before you sit back and relax all fall, check with municipal authorities to make sure you won’t be violating a local ordinance by leaving plant debris around. And be sensitive to your neighbors’ preferences; even if they don’t comment on your yard’s new look, take the time to explain why you’re leaving things au naturel this year. “Maybe they won’t get it,” says Tufts, “but at least they’ll know what you’re doing is done with foresight and not neglect.”
If you would like to help out your yard’s insect and spider populations, yet can’t bear the thought of looking at brown stems, just leave a section or two untrimmed. “Everyone’s tolerance varies a little,” says Tufts.
Many plants can look quite stunning when they bare it all for winter, and experts suggest cultivating some of them to enhance your yard’s off-season appearance. Long says sedums such as autumn joy are attractive, as are orange coneflowers and yarrows. Tufts recommends switchgrass and Indiangrass.
In addition to leaving plants standing, you can also help creatures by creating small brush or rock piles, or by cutting down some dead plants, then forming a loose pile of their stems on the ground. “Clipping is not necessary bad,” says Williams, “as long as you keep the stems in a place where the animals can extricate themselves the following spring.”
When spring finally does roll around, you may be tempted to run out and tidy everything up. After all, you’ve been waiting all winter. But try leaving a portion uncut all year, says Tufts. “Even if you hold off until April 1 and then trim everything, maybe 30 percent of the insects still haven’t emerged,” he says. “If you leave a little bit standing, then trim it next year and leave a different section standing, you’re always assured of doing your best in terms of perpetuating those species that may emerge later than most.”
Because many of the bugs that benefit from this approach are less than a quarter inch long, it may be difficult to observe the transformations taking place in your garden. Still, you will be making a difference. Changes will happen.