In many parts of New England, the trees are already shedding their wealth. Red maple, yellow birch leaves are beginning to fall, soon to be followed by russet oak foliage. Homeowners might savor the brilliant fall displays, but frequently they don’t value those leaves once they hit the ground. Rakes come out of sheds or landscapers appear with high powered blowers, and the fall foliage is either trucked away or piled on the back edges of the property.
It’s a shame, because these leaves are gold for your gardens. They are nature’s way of keeping soil fertile and organically rich. They are a plant’s tailor-made mulch. Yet homeowners typically get rid of this treasure and replace it with store bought mulches that have frequently been imported from Canada!
Research on the healthy growth of trees has shown that the best fertilizer and amendments for these plants is their leaves. Science proves what many would call plain old common sense. In the woods and fields, leaves fall, get compressed by snow and ice over the winter, and begin to decompose the following spring.
Gardeners and homeowners don’t usually want their entire properties to look like the woods and fields, however. Left as they fall, leaves blow about the yard, collecting in odd corners and piling up around shrubs or perennials. What looks natural in the woods appears messy in the home landscape. And those wet, compressed leaves can smother small plants and kill areas of lawn.
How to Use Fallen Leaves As Fertilizer
There are two possible solutions that allow us to keep the wealth of leaves while keeping our yards well tended. The first is to chop the leaves as they fall, and the easiest way to do this is with a lawn mower. Once the leaves are mowed and collected they can be evenly spread on flowerbeds, around shrubs, and, of course, under trees. The small chopped leaf pieces don’t blow away or form the same heavy wet layers that can suffocate plants.
Should you not wish to mow leaves or put them through a shredder, the second way of preserving leaves is to corral them in an open bin for summer camp. Think of this as a playpen for earthworms. A simple fencing enclosure, or even a box created of old shipping pallets will prevent the leaves from blowing with the warmth of the summer helps them to break down.
The key to success here is to water your leaf collection every couple of weeks should it not rain. Given a bit of moisture, the foliage begins to break down, aided by those earthworms. Turning it isn’t necessary since you’re not aiming to produce finished compost here. At the end of the summer the leaves will be partly broken down into what British gardeners call “leaf mold.”
Empty the bin before the next crop of leaves fall, spreading the dark, partly composted leaf mold around trees and gardens. Whether chopped or corralled for the summer, leaves are high in mineral content, are attractive as they age and will draw earthworms to your gardens. Best of all, as they decompose they add the organic materials that keep soils healthy.
Do you use fallen leaves as fertilizer?
This post was first published in 2016 and has been updated.
C.L. Fornari is the author of The Cocktail Hour Garden (St. Lynn’s Press, 2016) and several other books. She hosts gardening programs on WXTK and WRKO and gardens on Poison Ivy Acres on Cape Cod. Learn more about C.L. on her site, gardenlady.com.