Experts tackle readers’ garden questions.
Q: We have three tall redwood trees in our front yard. There is a lot of fallen leaves from the trees that have created a thick patch of mulch under the trees. Is it good to have that much mulch so close to the trunks? Should we be spreading them further away from the trunks so they will not get too wet? Or do we just leave all that mulch alone?
Betty Romeo, Fair Oaks
Sacramento County Master Gardener Cathryn Rakich: The fast-growing, long-living, ever-reaching redwood tree is a favored addition to many landscapes in the Central Valley. The fallen needles that pile up beneath these magnificent trees are a natural mulch and soil amendment that often provide all the nutrients the redwoods require. In addition, this natural needle mulch helps reduce water loss, regulates soil temperature and prevents soil erosion.
Because wet mulch piled up against the base of the tree trunk can lead to rot, it is a good idea to spread the needles at least two inches away from the trunk. But otherwise leaving the duff will provide the perfect organic carpet for your redwood trees.
Cathryn Rakich is a UC Cooperative Extension master gardener for Sacramento County.
Questions are answered by master gardeners at the UC Cooperative Extension services in Sacramento and Placer counties. Send questions to Garden Detective, P.O. Box 15779, Sacramento, CA 95852. Send email to firstname.lastname@example.org. Please put “Garden Detective” in the subject field and include your postal address. To contact UC Extension directly, call:
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