A protective covering, as of bark chips, straw, or plastic sheeting, placed on the ground around plants to suppress weed growth, retain soil moisture, or prevent freezing of roots.
tr.v. mulched, mulch·ing, mulch·es
To cover or surround with mulch.
[Probably from Middle English molsh, soft, moist (used of soil); akin to Dutch mals, soft, mellow, from Middle Dutch malsch; see mel-1 in the Appendix of Indo-European roots.]
The American Heritage® Dictionary of the English Language, Fifth Edition copyright ©2018 by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
The American Heritage Dictionary Blog
Check out our blog, updated regularly, for new words and revised definitions, interesting images from the 5th edition, discussions of usage, and more.