by Vancouver Island Master Gardeners Association
Question: Can I leave the leaves on my lawn?
The decision to not remove the leaves on your lawn depends on the number of leaves on the lawn, when you want to remove them, if you can use them as mulch on your garden beds, or if you have space to compost them. When not too thick a cover, leaves can be a wonderful source of nutrients for your lawn. You can leave a light covering of leaves over the winter.
Some people suggest mowing the leaves to cut them into small pieces while others suggest letting the leaves lie as they fall. Leaving the leaves in their entirety may lead to future advantages as many pollinators and small invertebrates hibernate in the leaves over winter. These insects will emerge in the spring and pollinate your fruit and flowers.
If the cover is thick enough to completely cover the grass, your lawn could suffer from lack of light and be susceptible to disease. In this situation, your lawn will do better if you remove some leaves. If you decide to remove your leaves, the best way is to rake them into piles while keeping the leaves whole rather than shredding them. Doing so ensures any insects overwintering in the leaves are not disturbed.
Once collected, spread the leaves onto your garden beds to act as a mulch over winter. The mulch can be 2 - 4 inches thick. Also make sure your smaller plants are not smothered by the mulch as they will need some light and water to survive the winter.
If you still have leaves left, you can compost your leaves in piles or in a compost system if you one set up. The compost can then be used to top dress your lawn the following years.