I can only say that we have bank voles. They go to Vegas especially celeriac and eat the middle right out leaving a thin shell. Could you have voles that are looking for food. To find out put an apple next to your plant and see if it’s eaten, they like apples. Val
As it's a new plant you may have brought the pest in with its roots. Go out at night and see if you can spot black vine weevil critters which would normally chomp foliage but their larvae will eat the roots so it's worth checking.
Vendée - 20kms from Atlantic coast.
"The price good men (and women) pay for indifference to public affairs is to be ruled by evil men (and women)."
I'll try the apple trick - we may have mice but I don't know about voles. I suspect it is something in the garden rather than something that came with the plant, as I bought a smaller gunnera once before and planted it in the same place - that also got eaten. I was hoping that a larger specimen (which the new one was) might withstand the munching.
I'll act detective tonight to see if I can catch anything at it but if it's anything with legs it will probably scarper as soon as I approach.
Whatever it is, I'm not sure how I could protect the plant against it (especially if it is squirrels, mice or voles). I haven't come across this problem with anyone else who grows gunnera.
Overnight update: the apple didn't just get eaten - it disappeared entirely by 11 pm. I suspect a local squirrel, fox (did I mention we have foxes?) or even our own labrador for that. No sign of any critters eating the gunnera (a few slug/snail trails late at night), but no sign of any fresh damage this morning either, so still stumped.
Fascinating. I know labs are good eaters but even they are unlikely to fancy a gunnera! I can't speak for squirrels and foxes but it seems far fetched.
That does look like physical damage, but I can't think what caused it. I suggest you take off the flower spike. Newly planted plants need to put their resources into growth, especially root growth, not reproduction. That will make for a generally stronger plant which will be better able to recover from the damage.
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