10/26/2025
Here is the monthly educational post from the Bellevue Tree Board:
Leave the Leaves
With cooler weather finally here, many of us are wrapping up the gardening season. A few chores remain—but one big question always comes up: what should we do with all those leaves?
First off, leaves are not trash. They don’t need to be bagged or hauled away. If you live in Bellevue or Omaha, you can send them to be composted—but why not keep those nutrients right where they belong? Leaves left in the yard add valuable organic matter to the soil and act as free, natural fertilizer.
Did you know that mulching leaves back into your lawn can return up to 3 pounds of nitrogen, 0.46 pounds of phosphorus, and 1.49 pounds of potassium per 1,000 square feet (Wallace, Vickie – UConn Extension)? Some researchers even suggest that mowing in leaves each fall could replace the need for a fall fertilizer or “winterizer” application.
At Michigan State University, researchers have been studying leaf mulching for more than twenty years. Their findings show no harm to turf—and in fact, an overall improvement in lawn health. One study even found that mulching maple and oak leaves reduced w**d populations, particularly dandelions. And don’t worry, shredded leaves won’t contribute to thatch buildup.
You can safely mulch up to six inches of leaves into your lawn, though most mowers aren’t built to handle that much at once. Try working with about two inches at a time, making multiple passes if needed. It’s normal to see bits of leaf material on the surface for a day or two afterward—they’ll naturally settle into the turf canopy.
If you have more leaves than your lawn can handle, mow and bag them for use elsewhere in the landscape. Shredded leaves make an excellent mulch in planting beds, while whole leaves are best avoided—they tend to mat down like pancakes and block water and air. In vegetable gardens, either whole or shredded leaves can be turned into the soil to enrich it for next year’s crops.
For residents of Bellevue, excess leaf litter can also be placed in the brown yard waste cart for collection and composting through November 30th.
Nationwide, yard waste makes up roughly one-fifth of all landfill material, and bagged leaves account for nearly a third of that total. By keeping your leaves on-site—or composting them through the city’s program—you’ll nourish your landscape, reduce waste, and help support a more sustainable Bellevue community.
