This time of year, we typically would be enjoying a great fall display of reds, oranges, and golds, yet the show seems to have just begun for most trees here in northern Illinois. As soon as we get nights of below freezing temperatures or big winds, it all will be over. The weather and timing may be different this year, but we have the same challenge: what to do with all those leaves.
If you are out in the country with natural woodlands, leaves play a critical part in preserving the natural habitat of native trees, shrubs and flowers. If that is the case, just let those leaves lie. The leaves will decompose and return valuable nutrients to the soil. They will be used by the soil microbial life that in turn support plant growth.
Where your lawn and trees exist together, mulching the leaves with a mower lets the small pieces fall between grass blades, benefiting the soil, trees and lawn. At some point, there can be more leaves than can be mulched in; this is the time to mow and bag them so the leaves do not smother the lawn.
Where the vegetable garden is adjacent to the lawn, consider either mowing or blowing the leaves in to the beds to be worked in yet this fall or left as a mulch layer for the soil to be worked in next spring. Whole leaves can be used as mulch around the base of tender plants like roses. You use the whole leaf so as mulch it does not pack down defeating the purpose of protecting the crown of the rose plant.
Now back to the leaves you have collected with the lawn mower. Consider using them to start a compost pile or build upon the one you already have, or use a compost bin. That mower bag contains two primary ingredients, browns (leaves) and greens (lawn clippings). The traditional compost pile will need to be four to five feet square at the base to be large enough to support composting with a height of about four feet, so you do need some space.
As you create the compost pile, some garden soil should be sprinkled in as you go to provide the pile with the microbes that will be breaking down the organic matter into compost. Since organic matter is naturally acidic, about a half pound of a finely ground limestone also should be added for every cubic yard of material. Now, your compost recipe is almost complete. Once the composting pile has been created or the bin filled, the final ingredient needed is water. If the pile/bin remains too dry, no breakdown occurs. If left too wet, an anaerobic condition and decay occur, giving you a very smelly, slimy mess to deal with.
Fresh kitchen produce peelings also can be added to the compost pile year round. They provide some of the moisture that is needed during the summer and after they have frozen and thawed from the winter months, provide moisture as well. If you are lacking in the fallen leaves department, just ask the neighbors who have bags sitting out at the curb. Do not let that good organic matter get away, build a compost pile, add to it or fill the compost bin you already have.
About the author: Richard Hentschel’s expertise extends across several subject areas with specialties in lawn care, fruit tree production, woody ornamentals, and home and community gardening. During his 45-year career in horticulture and agriculture, Hentschel became a well-known and respected expert for commercial and homeowner audiences, industry organizations, and media. He retired from University of Illinois Extension in April 2022 with nearly 30 years of service as a Horticulture Specialist and Educator in northern Illinois.