Mulch for Rhododendrons


What is the best mulch for my rhodos for over the winter? I don’t have access to oak leaves, and I do have some pine needles (but not enough to make any depth of layer). Can I use cedar chips (from the pet store)? Would straw work? I think the soil is clay to loam, and they never get full sun. Thanks, Sandra


This is a great question, Sandra. Rhododendrons most certainly benefit from mulching because of their shallow roots.

Rhododendrons do best when they have about a 2″ to 3″ layer of mulch to hold in moisture, prevent weeds, and keep the roots cool. Since most mulches are organic, they need to be topped off periodically, usually about every year or two. Do not make the mulch over 3″ thick. Keep the mulch about 2″ to 3″ back from the trunk/stem of the plants to avoid bark split and rodent damage.  It is best to mulch with a 2-inch layer of an airy organic material such as wood chips, ground bark, pine needles, pine bark or rotted oak leaves. A year-round mulch will also provide natural nutrients and will help keep the soil cool and moist.

The following article is written by a Canadian for the American Rhododendron Society. Mulching suggestions include coffee grounds, sawdust, bark mulch, needles and small twigs and seaweed and straw.

Good luck with mulching your rhododendrons.