This pest turned up in a downstairs room next to the greenhouse late winter a couple of years ago, and munched some bush beans I was growing. I thought it was a bean pest, and I have not seen many of them nor a lot of damage to worry about until last year. My Swensons grape got severely eaten. And this winter I've seen the same kind of leaf damage on some cabbages in pots in the house. So it's time for me to make my to-do list and get rid of this pest once and for all, if I can.
Anyone else have experience with the vine weevil? I thought it would be a southern pest but it turns out that it is fond of rhododendrons and common enough outdoors here. So it is not exclusively a greenhouse pest, but it does take advantage of greenhouses given the chance. Not only the adults feed on leaves, but the grubs feed on roots and can kill your plants! I have a few perennials that are permanent greenhouse residents, and I'm not willing to give up on them. These weevils gotta go!

Here are a couple of articles by Richard S. Cowles that describe the life history of this pest Otiorhynchus sulcatus in great detail.
https://scholar.lib.vt.edu/ejournals/JA ... cowles.htm
https://www.rhododendron.org/v57n4p219.htm
I will need two strategies, one for adults and one for grubs. The adults are all female! Parthenocarpic and layers of eggs. When you see heavy feeding, egg laying will soon follow. The adults mostly feed at night and hide during the day. It may be possible to trap them. I will also look for them when I clean up the leaves that are now lying in the greenhouse where they fell, because dry leaf litter or mulch is another place they may hide. I'm going to try cleaning off all the soil from my two cabbage crosses (which I was hoping to get seed from) and look for grubs and root damage, then repot them.
As for the perennials which I can't shake out and repot, I may have to try nematodes - Cowles says "black vine weevil larvae are susceptible to virtually any commercially available species, including Steinernema carpocapsae, S. feltiae, and Heterorhabditis bacterio-phora ". I believe they are temperature sensitive though so I will have to check that out and time it accordingly. And get a soil thermometer!

Early April, I had to pot up my Eleuthero which already has green tips ready to emerge. It was very rootbound so I watered well and pulled the roots apart. In the end I found and destroyed about two dozen of these nasty grubs, all in about 4-6 inches depth and just ready to chow on my precious roots. So the timing is right and I expect to find even worse on the grape. If it warms up enough, I'd like to strip the soil off it outdoors, and leave the grubs for the birds.

Ah geesh we have those, I always thought they were just another beetle. That may be what helped decimate my tomato plants last year. May have to try your nematode solution, if you have any luck with it.

Looks like Botanigard/Mycotrol works, I know it's expensive. I believe you can use it as a soil drench also (unless I'm confusing it with another product), so you can spray for the weevils and soak for the grubs...I guess it works for the grubs, maybe not.

https://www.arbico-organics.com/product ... ls-control

Yeah, thanks for the reminder there is something biological out there that might work. I was planning to get some BTK as well, see if it solves the little moth problem I seem to have - that is nasty for tomatoes! But I bet the grubs are as well. I didn't see evidence of grubs on the tomatoes when I pulled the roots, but the grape did really poorly and was being munched by adult(s) as well as grubs doing the roots - I have no doubt it's fully infested.
I am down to physical methods for now - not willing to order anything from away until I see evidence that the postal service is working again.
Since the adults don't fly, there seems to be some talk that barrier methods and traps can work. But I certainly saw them up in the canopy so there is no doubt they can go places by crawling and climbing. Anything touching the wall is trouble....
It is really a shame that it's still too cold to leave the grape outdoors.
We have a big Carabid beetle in the garden that eats pests like these suckers and their grubs!
OTOH maybe it's good to keep the grape inside as bait. I really don't want this pest on any of my medicine plants. Have to check and repot my japanese honeysuckle too. But no way I can repot or disturb the roots on my eucommia tree. So the nematodes or Botanigard may be the only answer to that.
I've been watching for adults and checking places they might hide - removed all the mulch and leaves, but came up negative so far. I thought there was one on my brassicas indoors this winter, because I saw signs of munching on the leaves. But I have failed to find one adult culprit yet.