A friend of mine has a 2 by 10 foot edging of rocks in his yard. He wants to grow flowers there. The rocks are standard, small river rocks. Underneath is a weed barrier. Would it work to simply build a sheet mulch right over the rock as is, or would it behoove us to do the extra work and remove the rock and barrier? If he wanted to grow plants for food or medicine, I’d definitely vote to do the work. But since it will be for show and pollinators, it may not be worth the extra effort. What do you think? If leaving the rocks/barrier would be fine, how high do you think we would need to build the sheet mulch in order to not compress the roots? Thanks for the wisdom.
Howdy Paul, welcome to permies!
I have rock areas under large trees that are covered with leaves every fall. The soil is slowly accumulating and the grasses and "weeds" are moving in.
So yes it can be done . The real problem here seems to be more the paper than the rocks. The roots have made progress in some areas , at getting deeper than the paper, but generally stay on top of the paper.
Seems like that stuff lasts a long time.
So you can remove the paper and have deep roots or pile up the soil on top, ( better yet a hugel!) and give the roots room to grow.