A large percentage of landscape waste comes from grass clippings, tree leaves and other gardening debris. Tree leaves make up half of that waste. Those fallen leaves are a valuable natural resource and should be managed and used rather than bagged and placed at curbside to be picked up and hauled to local landfills.
Leaves are packed with trace minerals that trees draw up from deep in the soil. When added to your garden, leaves feed earthworms and beneficial microbes. They lighten heavy soils and help sandy soils retain moisture. They’re a fabulous source of carbon to balance the nitrogen in your compost pile, and they insulate tender plants from cold.
Consider these ways to use leaves in your landscape, reduce your gardening costs and protect our environment:
On the lawn
Start mowing and shredding the leaves as soon as there is a thin layer on the lawn. Set the mower at its highest setting and mow as usual. Then mow in the opposite direction, making a crisscross pattern. You will get a faster green-up of your grass next spring while using less fertilizer because the small decomposing leaf pieces provide nutrients to your lawn over the winter. This also helps with weed control as the decomposing pieces of leaves cover up bare spots between turf plants that are an excellent opening for weed seeds to germinate.
On trees, shrubs and flower beds
If a total leaf fall occurs and there are too many leaves to mulch as previously described, another option is using your mower to bag the leaves for use around flower beds, trees, shrubs and vegetable gardens. Leaf mulch reduces evaporation from the soil surface, moderates soil temperatures, keeps soils from eroding and crusting, inhibits weed growth and prevents soil compaction.
As they decompose, they release valuable nutrients for use by your landscape plants. Apply a 3- to 6 inch layer of shredded leaves around the base of trees and shrubs. In annual and perennial flower beds, a 2- to 3-inch mulch of shredded leaves is ideal. Mulches are especially beneficial when used around newly established landscape plants, greatly increasing the likelihood of their survival.
In vegetable gardens
Apply a 3- to 6-inch layer of mulched leaves onto the soil surface to reduce topsoil erosion and add valuable organic material that microorganisms will use throughout the fall, winter and spring as shelter and food. Next spring, lightly turn this mulch into the soil or plant directly into it or beneath it, depending upon whether you are seeding or transplanting. Also, a thick layer of leaves placed between the rows functions as a mulch and an all-weather walkway that will allow you to work in your garden during wet periods.
Another recommended strategy for using leaves to improve soil in vegetable gardens is to collect and work them directly into the soil during the fall. This allows sufficient time for the leaves to decompose prior to spring planting. Adding a little fertilizer to the soil after working in the leaves will hasten their decomposition. A 6- to 8-inch layer of leaves tilled into a heavy, clay soil will improve aeration and drainage. The same amount tilled into a light, sandy soil will improve water and nutrient holding capacity.
Autumn leaves can be appreciated not only for their brilliant colors, but for the many benefits they provide to gardeners.
When you have questions, Colorado State University Extension has research-based answers. The Help Desk is open at 17 N. Spruce St. Hours are 9 a.m. to noon and 1 to 4 p.m. Mondays and Wednesdays. Call 520-7684 or email CSUmg2@elpasoco.com.