(Article Updated 10/18/23)
This time of year, we receive questions about tree leaves on the lawn.
Essentially the questions consist of, “Should leaves be kept on the grass, removed completely, or mulched?”
Some of these questions come from customers with newly installed sod, others have established sod that was installed a while ago, and still others were calling about their lawns that were established by seed.
No matter the origins of your grass, and no matter the age of your lawn, at Red Hen Turf Farm we do NOT recommend letting your leaves cover up your grass throughout the entire winter.
Yes, if you do enough Googling, you’ll see articles that tell you it’s desirable to let the leaves stay there, mainly because a thick layer of leaves gives wildlife a nice place to live and find food.
We generally disagree that leaving all (or the majority) of your leaves on your lawn over the winter season is a good idea — especially if you are aiming for a healthy, attractive lawn.
In fact, we recommend you limit the advice you get online to reputable, regional websites such as Purdue University Extension, Michigan State University Extension, and Ohio State University Extension. At times, we also might use extension.org and other “land grant university” websites, although we try our “local” sources first.
When we give advice to our customers, it’s typically based on these “land grant university” / Extension websites because they only publish information that is backed up by scientific research and they pass the so-called C.R.A.A.P. test, which means they are Current, Relevant, Authoritative / Accurate, and their Purpose is to provide science-backed information to the community and to fellow experts.
University of Minnesota Extension suggests that IF you MUST allow leaves to cover up 10-20% of your lawn, it MIGHT be fine … but allowing more than 20% of your lawn to be covered by leaves over the winter is an EXCESSIVE amount and is not advised.
WHY NOT? Many reasons, including:
- Excessive leaf coverage over winter will likely smother your grass and inhibit growth in the spring.
- Leaves shade your grass, which can prevent your lawn from being able to photosynthesize in the late fall. Photosynthesis is crucial for plant growth because it’s the process that let’s them turn sunlight into “food”.
- Thick layers of leaves can smother and completely kill your grass. Removing the interference from fallen tree leaves also allows your late season nitrogen applications to reach the turf more effectively, and improves the efficacy of late-season broadleaf herbicide applications. Therefore, for optimum turf health, it is critical to remove the tree leaves, or at least break them up.
- Leaves, even in small amounts, can trap humidity at the surface of your turf, which may encourage snow mold diseases.
- Nuisance animals — like mice, moles, and voles — quite enjoy living in leaves, and may cause more turf damage than usual. (Yes, some people believe that giving these animals a winter home by leaving your leaves on your lawn is a GOOD THING … but you have to weigh the pros and cons for yourself.)
So, what might you do with your leaves?
- Rake them up or use a leaf blower, and then either compost them, dispose of them, or use them to mulch a non-turf area of your landscape such as your garden of flower beds.
- Use your mower’s bagging attachment, then either compost them, dispose of them, or use them to mulch a non-turf area of your landscape such as your garden of flower beds.
- If the coverage is no too excessive, you can MULCH your leaves with a mower, a dedicated “leaf mulcher” tool, or even shred them up a bit using a weed whacker / string trimmer. This chops them into smaller pieces that won’t smother your grass, and will decompose quicker than whole leaves. Mulching is an especially good way to handle autumn leaves since the nutrients and organic matter will benefit your lawn and soil. To learn more about mulching leaves check out THIS LINK from the City of New Rochelle, New York, which provides information from Purdue and Michigan State Universities.
Until next time!
And keep the questions coming via email at turf (at) redhenturf.com – by phone at 574-232-6811 – or even by text at 574-766-7633.
… from The Red Hen Turf Farm Crew.