Thanks for that post @glasgowdan, I was wondering what the effect the vinegar mix would have on the "weeds", we were going to spray a small area of the driveway and monitor the effect before spraying the whole lot.
I have used a pelargonic acid based weedkiller fairly successfully in the past. This is harmless to wildlife and doesn't damage the soil. It is made from a substance found in Pelargonium leaves.
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