Posted: 08/01/2015 at 10:18
Nematodes work well in open ground, provided its not really heavy clay and you keep it moist. Have a go in April (I treat mine April and October to keep at bay).
I don't like provado (sorry verdun!) but resorted to using it in a few non-flowering/non-pollinated pots last year, as the nematodes weren't happy there (too hot and difficult access for me to water). So long as bees and other pollinators are not going to be affected, I'm ok with that, just...
Good idea to crush beetles at night - but they're damn fast, so be aware! Takes some practise .
Very good idea to clean the soil off really affected plants and repot, if potted. Grubs can be huge, particularly if the winter has been mild (again) and often no adults have been killed off and the larvae have really grown well. Yuk.
Bear in mind that it's usually about controlling your problem with weevils, rather than total elimination - simply because your garden is likely to be affected by pests from other gardens, so unless everyone treats weevil, the blighters will always be there.
I find that twice yearly nematodes, a tiny bit of provado in the right places and vigilance,e as others have said, controls the problem to a point that it doesn't bother me much, but I know that the weevil will never be wiped out in my garden either.