I have been battling virginia creeper, grape vines and wild violets in my lilacs. My lilacs are mature and line my backyard lot line. (the row is about 15 feet deep by 10 feet long) I have been fairly successful by pulling out the vines and they have significantly diminished. Grass does not grow in the undercanopy and I would like to bring in fresh dirt mixed with compost to even out the area.
My question is, can I safely use a water permeable barrier around my lilacs? I would like to put down mulch and plant some ferns and hostas and other plants that will do well in the shade. What type of mulch would be safe to use over the barrier?
Any suggestions would be appreciated.