While planting natives is an essential step toward creating habitat, how we manage our plantings will determine whether we can sustain and support the life-cycles and successful reproduction of many other organisms including birds, butterflies, moths, bees, salamanders, and frogs.
Autumn is when many of us think to put our gardens to bed by removing leaves and cutting back perennials. Yet to truly support living creatures year round, it’s much better to leave fallen leaves, branches, stems, and seed heads where they are rather than raking, blowing, shredding, or cutting them away. Leaves and other organic matter insulate plant roots through the cold winter months and then decompose to build up living soil critical to healthy vegetation. This organic matter also stores large amounts of carbon, which is crucial to a resilient planet in the face of climate change.
Rethink your “clean up” this year – take inspiration from the following ideas to manage your leaves and other natural materials in fun and creative ways while protecting creatures all year long.
Many species of butterflies and moths, including our beloved luna moth, pupate and overwinter in leaves before emerging as stunning winged adults the following spring. Raking away the leaves is very disruptive to that life in the leaf litter. Leaf blowers are even more damaging, and also create noise pollution and use large amounts of fossil fuels – please discontinue this practice.
Undisturbed leaf litter is also essential to the Baltimore checkerspot butterfly, which requires two seasons to complete its life cycle. After a first season of foraging on its host plant (white turtlehead) the caterpillars crawl down and overwinter in the leaf litter. This once common butterfly is in decline due to loss of habitat and poor gardening practices.
Other small creatures like the eastern newt, as well as many species of salamanders and frogs, spend the frigid winter months hibernating under the protection of leaves, rocks, and logs.
For many, leaf management can feel like a never-ending burden in the fall. Even if we want to leave the leaves, we can’t let them accumulate everywhere or they will smother the grass, clog sewer heads, and leave a slippery layer to get mushed into the ground by cars, snowblowers and pedestrians.
The problem is not that deciduous trees shed “too many” leaves, but that we have developed our landscapes and removed natural areas. Too much space is now taken up by driveways, streets, sidewalks, and lawn.
Leaves are an exceptionally valuable resource! They contain nutrients and organic matter that we should keep on site, instead of raking or blowing them from off our lawns and driveways and into the woods, or stuffing them into leaf collection bags to be taken off site. We can find more places for the leaves to go by shrinking our lawns, creating more planting space, and consolidating the excess leaves that fall outside our planting beds.
Using leaves as mulch for a planting bed is a free alternative to buying bark mulch or other expensive and harmful inputs such as fertilizers and dyed mulches. The space under a tree is an especially critical place to keep leaves since many butterfly and moth caterpillars drop down from trees into the leaf litter to pupate and overwinter. Let’s do what we can to keep this colorful natural blanket where it falls.
After shrinking the lawn and expanding planting areas, there should be more room to accommodate the leaves removed from the remaining lawn and driveway.
Still too many leaves? Rake the leaves that fall outside the planting beds into a pile. Yes, in this case raking is okay (and leaf piles are necessary for jumping in!). Our goal is to not remove them from within our planting beds, which benefit from the organic matter and insulation for the cold winter months, limiting disturbance to the leaf litter and any overwintering creatures.
Move your leaf pile somewhere it can compost in place over the next growing season. You will be surprised by how quickly it shrinks down. Or, make a leaf fence! Coil up chicken wire into columns and arrange them side by side. Fill them with leaves. You’ll find that you can’t use the leaves up fast enough since they break down so quickly. Before you know it you’ll be stealing the curbside leaf collection bags from your neighbors to keep your leaf fence full. Suddenly one person’s yard waste is another’s treasure.
While it is best for overwintering creatures to compost leaves from your driveway or lawn, shredded leaves do make a beautiful looking mulch for a more traditional planting bed. Shredding leaves does destroy the small creatures, but is a somewhat fair compromise for situations where a more tidy look is demanded by a homeowner. If you are looking for more formality, but want to do less harm, make sure the edges of your planting bed are well-defined, while keeping the interior relatively untouched.
Of all the shredders on the market, an electric vacuum shredder leaves the lightest carbon-footprint. Or, you can simply rake a pile of leaves in the lawn and mow over them several times, then toss them back into the garden bed.
Inevitably, leaves will blow around and pile up in various corners of the yard. Rather than repeatedly removing leaves from the same spots, pause and pay attention to where they tend to accumulate or blow away, and plant accordingly.
Plant strong stemmed plants like ferns, baneberries and bugbanes, coneflowers, or milkweeds in the areas where leaves accumulate. Leaves often form a deeper layer in low, concave spaces of the landscape, like at the bottom of a slope or a valley.
There are a few ground covers like sedges, creeping and rock phlox, pussytoes, bearberry, and groundsels, that can get smothered by leaves. Plant them in spots where the wind strips leaves away. Leaves don’t tend to stay put on elevated, convex landforms, so don’t fight it and work with what you have.
Wait until spring, just as you begin to notice sprouting and emergence, to remove leaves that get stuck in the crevices between rocks, against fences, and within shrubs.
A common worry of gardeners is that plants cannot push through whole leaves or thick layers of leaves. Many woodland natives, even ephemerals like trout lily and squirrel corn, that are adapted to soils rich in organic matter created by decomposing leaves, have no trouble emerging through a good 2-6” of leaves.
In addition to leaves, avoid over-removing items like sticks, stumps, and logs. Gather materials that may look haphazard (to some) into intentional piles or arrangements to be enjoyed by all. Frogs, salamanders, as well as fungi and other decomposers, like beetles and millipedes, all benefit from the extra opportunities to nest, feed, and overwinter in this woody debris. This can be done on a small scale in a suburban yard or applied to a rural woodlot. Gary Smith’s “Hidden Valley” sculpture at Garden in the Woods in Framingham, MA illustrates this concept most elegantly with an undulating line of fallen longs.
Leave stems and seed heads of grasses, coneflowers, asters, and other herbaceous plants to sustain pollinators and non-migrating birds through the winter. Pithy or hollow stems of plants like Joe-Pye weed, flowering raspberry, and black elderberry, left up or cut back to at least 18”, provide perfect chambers for many of our native solitary bees to lay their eggs in, which hatch come spring. They are also beautiful covered in frost and snow.