Question: At my new home there's a large population of vinca underneath some deciduous trees. Do I have to gather the tree leaves off of it this fall, or can I leave them to decompose?
Answer: It is best to remove fallen leaves from atop groundcover plants. If the leaves are left there, they can keep things damp, which is just the sort of condition in which diseases like to grow and overwinter.
To remove the leaves without ripping up the plants, gently use a rake or a leaf blower. You can then shred the leaves with the mulching attachment of the leaf blower or by running over the pile with a lawn mower. Blow them or spread them back over the groundcover. They'll slip down between the plants and decompose to feed the soil—much more quickly and with less risk of disease than whole leaves would.
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