Lava Rock as Mulch
I have a semi-sloped garden and am using Lava Rock as a mulch. I find it helps with erosion issues as well. Are there any negatives to using Lava Rock as a mulch? The only reason I ask, is everyone thinks I'm crazy when I let them know what I'm using. Also, is there a difference in the black and red, other than their color? Thanks for any help!