The weeds have completely taken over
There is one technique here that is dramatically better than the others and most people have never heard of it: cover the ground with an opaque tarp and wait.
What actually works
An opaque silage tarp held down tight. Virginia Tech trials killed some annuals in **2–4 weeks**, and found **perennial weeds killable in half a growing season** rather than a whole one. Tough species like bermudagrass need longer. It is the highest-return weed technique there is and it costs one tarp, reused for years.
Prepare the bed two to three weeks early, let the first flush germinate, then kill it shallowly without stirring up new seed. You plant into ground that has already spent its ammunition.
Four inches suppresses most annuals. Against the stem it's a slug hotel and a vole tunnel.
The oldest line in gardening — one year's seeding, seven years' weeding — and it's arithmetic, not folklore. A single pigweed makes well over 100,000 seeds.
It burns the top off and the root laughs. Fine on a crack in a driveway, useless on bindweed or bermudagrass — and 20%+ vinegar burns eyes and skin, so it isn't the gentle option it's sold as.
Weeds root into it from above, it tears, and in three years you're picking shredded plastic out of your soil forever. Tarps come off; fabric stays.
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weeds out of control · overgrown garden · bermudagrass · bindweed · kill weeds without chemicals · cardboard mulch · landscape fabric · vinegar weeds