My sister-in-law has some blackberry bushes that are against a wire trellis. Where the bush touches the wire, it dies. Not sure what the wire is made of.
Do You Know if Blackberry Bushes Don’t Like Certain Metals
Certified GKH Gardening Expert
I do not think it is metal toxicity at play here. I believe that the foliage die back you are seeing is because metal is a cold conductor. The foliage touching the cold is dying.
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