I used shredded cedar mulch last year. Should I clean out all the old mulch before putting down new mulch? Can I leave the old mulch in place and mix it with new mulch?
Thanks for contacting Toronto Master Gardeners.
Yes, you can and should leave the old cedar mulch in place–it will gradually break down. You do not need to clean out or replace the mulch. Simply add new mulch–you can mix it with the old, but it is not necessary. Be assured that you are using good gardening practices by using mulch in your garden–mulch helps to suppress weeds, to moderate soil temperatures and to conserve soil moisture. When you put down the mulch leave a bit of space around trees and shrubs so the mulch it not up against the bark. This improves air flow and avoids damaging the trunk.