Garden Q&A: Mulch volcanoes are not what nature intended
By Ellen Nibali
For The Baltimore Sun|
Apr 12, 2018 | 9:00 AM
I've been getting teased about making mulch volcanoes. They look good to me. What's the big deal?
Mulch volcanoes, with the mulch being the volcano and the tree being a vertical column of lava, are not what nature intended. Nature mulches with leaves or needles, when she mulches at all. Humans mulch to keep lawn equipment from damaging bark, to prevent weeds and help keep moisture in the soil. Ironically, light-moderate rain won't penetrate a deep mulch volcano, and worse, fungal mycelium decomposing the mulch can create hydrophobic mats that repel water. Not what humans intend. We recommend mulch about 1 to 2 inches deep and several inches away from a plant base so pest insects and voles aren't attracted there. For a more solid weed barrier, spread several layers of newspaper under the mulch. It still looks good.
I plan to apply corn gluten to prevent lawn weeds. Is this a good way to prevent weeds naturally?
Corn gluten has not proven to be a very effective pre-emergent and requires several years of application to build up effectiveness. Then it becomes a problem if you need to overseed your turf. It also releases nitrogen, which makes it a fertilizer and must be counted in your fertilizer quota for the year. Applied at labeled rates, it can exceed the amount of nitrogen permitted in Maryland. A simple approach to weed prevention is to use thick turf to crowd out weeds and shade out weed seed germination.
University of Maryland Extension's Home and Garden Information Center offers free gardening and pest information at extension.umd.edu/hgic. Click "Ask Maryland's Gardening Experts" to send questions and photos.