Posted: 11/06/2014 at 14:20
Sadly I have some experience of these nasty little critters, which often over wintered very nicely in my London garden...
they usually overwinter as grubs, then (unless it has been a very mild winter, in which case they could be destructive earlier), they'll usually become active in Spring, eating everything they can find close by. Apparently they don't travel far from the host plant mummy laid them in
They then hatch as beetles over the summer and start laying eggs - up to 1000 a season. The bad news is that they're also all females!
so by spring, the grubs are nice and plump, getting plumper by the day and raring to go - that's why nematodes work best then...and in autumn to catch the early young grubs or the other ones from spring you may have missed.
I profoundly hate them.
can you tell?
But I have to say that if you keep on top of them twice yearly with nematodes, it does work.
i also use provado but ONLY on containerised plants (particularly vulnerable to weevils) and only for non-edibles and plants that are not pollinated or don't have obvious flowers. I am very scared of harming bees and this is the first year I have used provado (I blame Verdun, who swears by it ) in my life.
but I did get very sick of seeing more vulnerable plants die...not from weevil necessarily, but all- round 24/7 attack by RSM, leaf miners, aphids and everything. Fed up!