mulch?

Round-up. Or a torch-thing that I found in one of the garden catalogs - I think they all sell them. I use it mostly on the patio stones for the stuff that occasionally sprouts You could also dig about 6 inches deep, a trench - any width from about 3" to 6" and fill it with sand, stone, then an inch or two of mulch. Angle it in toward the stone wall and go straight down from the wall. We did this - although we first lined it on the bottom and up the sides almost to the top with landscape plastic, then filled almost to top with sand, then an inch of mulch so it looks good. Very little weeding now. Just a spray of Round-up occasionally. Lawnmower wheel fits into the 'space' easily.

Westy1941

Roundup is what I use in paths and different places where I don't have grass growing. It kills in about 2 weeks and lasts all summer long.

If your string trimmer can handle it, use a heavier duty line. Be careful, though, and make sure you wear safety glasses when you're using your string trimmer around stone.

Thanks to all of you for your help. A 6-8 inch bed of mulch would look good. I think that I will be able to get a handle on the problem during the winter and it won't get out of control again next summer.

I took a different tack -- last summer I deliberately planted a 6" double row of groundcover plants at the base of my curved knee-height walls (made of stacked slabs of broken concrete) -- ajuga in the shady areas, and violets in the sun. Both made nice low lines of dark green to contrast with the pale-grey concrete, smother (other) weeds, don't need weedwhacking, and don't take any harm if the lawnmower runs over their edges. And they bloom, too. These plantings are now a year old; the ajuga is less thick than the violets so I've had some trouble with dandelions there (this was a very dry summer) but neither are doing much (yet) to invade either the lawn or the beds above the wall. I'll let you know in another year or so how it looks longterm, but so far it's cut my workload considerably...

FWIW.

LynnT