how often are we advised to cover the ground for a season or two to kill weeds? I have just dug up massive heap of old soil with a large sheet of tin at the bottom. Even after 20 years and under 2 metres depth of earth and metal, the first thing I saw on lifting the tin was a monstrous tangle of vicious white bindweed roots - just getting ready to spring into furious growth. So, covering the ground works maybe, if it is a permanent cover, but as a weedkiller.....well. the jury is still out I think.
bindweed truly the work of the devil. In my old garden it was daily chore going out to see what was being murdered by it! We did every thing imaginable to it to no even semi permanant result. None on my current lottie-couch grass seems like a baby in comparison!
If the shoots can come up round the tin it will have had no effect, except allowing the roots to build up without disturbance!
:(
Couch grass is a walk in the park compared to many of these weeds, it just looks daunting. I got rid of my plots infestation in 1 year.
Campanula, I had a similar experience when I took over Charlie (my plot) last April. As I was turning the soil I hand picked the streamers of bindweed roots. I noticed that some were white and some brown. Made no difference - out they came. Later, an older wiser person approached and asked me if I was sure I didn't want the long established asparagus bed...
...NNYYYAAAAAAARRRGGHH!!!
:'(