fbpx Let Those Leaves Lie | The Morton Arboretum

Let Those Leaves Lie

Fall leaves on the ground
October 1, 2019

The leaves are falling! It’s time to start the arduous process of raking and bagging leaves, or hire someone to do “fall cleanup” to make the yard tidy.

But what if you didn’t? What if you kept the leaves in your yard? You’d have healthier soil and happier plants, that’s what.

Trees and other plants evolved to live in soil that is continually enriched by the leaves and other plant matters that die every year, according to Meghan Midgley, soil scientist at The Morton Arboretum. The soil is full of fungi, bacteria, worms, and other organisms that will readily digest the leaves, making the nutrients they contain available to plants’ roots. When we remove the fallen leaves from the garden, we’re throwing all that nutrition away.

Here are some tips for being smart about fall leaf cleanup:

  • Use the leaves for mulch on perennial beds or around trees and shrubs. Just rake them where you want them to go. Most of them will be gone by spring—evidence that the decomposers in your soil have been hard at work. 
  • Add leaves to the compost pile, where they are an important carbon source. The most efficient compost pile will have far more leaves and other brown, carbon-rich materials than green, nitrogen-rich materials such as green plants and vegetable scraps. 
  • Shred leaves into small pieces and they will break down faster in the compost. They also won’t blow around as much when used as mulch. It’s easy: Just rake them into a pile on the lawn and run the lawnmower over the pile a couple of times.
  • Rake whole leaves off the lawn so they don’t form a mat over the grass all winter. It’s fine to scatter some shredded leaves there; in fact, they’re good food for the microorganisms that live in the soil and nurture the grass. 
  • If you don’t have a compost pile, leaves make autumn the perfect time to start one. Rake up a big pile of leaves and mix them with green materials—end-of-season annuals from your pots, the remains of the vegetable garden, fruit and vegetable scraps from the kitchen. Stir in a shovel-full of soil from the garden to provide the fungi and microbes. Water the pile occasionally to encourage microbial activity.
Tree and plant questions? Turn to the experts in our Plant Clinic