Fall mulching provides multiple benefits
Q: My neighbor always mulches in the fall. I thought mulching was done in the spring. Does he know something I don’t?
— Seth from Mineral Ridge
A: A lot of people consider mulching a one-time activity done in the spring, when, in fact, mulching is a continuous activity and fall is one of the best times to do it.
The main purpose of mulch is to keep soil temperature and moisture levels constant. It also suppresses weeds and over time, as the mulch decays, provides nutrients and organic matter for the soil. All these benefits are as important in the fall, as in spring. And for some types of plants, fall mulching is especially important as we’ll see.
Mulching in the fall insulates the soil environment, keeping it warmer for earthworms and soil microbes, which is good for soil health. The mulch insulation keeps the plant’s roots warmer, allowing the roots to keep growing longer into the fall. This promotes a stronger plant next spring in addition to slowing the cooling of the soil into winter.
Fall mulch will help prevent frost heave caused by the winter freeze and thaw cycles. Frost heave can damage or kill perennials.
If you have evergreens, fall mulching is very important. To keep their leaves (needles) alive during the winter, evergreens need a constant source of water. When the ground freezes the source of water is cut off. With no water, the leaves and eventually the stems begin to turn brown and die, a condition called winter burn.
Each spring we get questions in our clinic about evergreens turning brown, and the reason for the browning is mostly winter burn. To mitigate winter burn, mulch around your evergreens and if needed water these shrubs up until the ground freezes. Fall watering can do a lot for your plants in addition to the mulching.
You can use the same materials for fall mulching as you do in the spring. Plus, in the fall most people have access to a great source of free mulch — fall leaves.
Shredded fall leaves make excellent mulch, and a lawn mower is a good way to shred them. Mow the leaves and then spread them over your flower beds or garden. And since leaves don’t have any seeds, you don’t have to worry about adding any weeds. Whatever mulch you use, don’t over apply it. Two to four inches of mulch is fine.
No flower beds or garden? Mulch your lawn by mowing the leaves into the grass. This will add nutrients to the yard’s soil and suppress weeds. A study by Michigan State found mowing leaves into the yard produced a faster green up next spring and nearly a 100 percent decrease in crabgrass and dandelions after three years of mulching.
To learn more about turning leaves into gold this fall, go to http://go.osu.edu/leavessave.