Hi

Have you read it correctly as it states :

"It can be used from April to September. April and August/September are the vine weevil's main egg-laying times"

Use nemesys - can be applied when the temperature is 5 degrees C but works better if its warmer. Recommendation is its most effective used in August/September, but you can use it now too see here

https://www.greengardener.co.uk/product.asp?id_pc=22&cat=46

I have a similar problem with my Heucheras. Devastating. My present solution is as follows:
1. Pick out the grubs and feed them to the birds. (Alternatively, just kill them.)
2. Not wanting to throw away good compost which may, however, house more grubs, I put the compost into a watertight container and pour in water until it is just above the soil level. Leave for several days, maybe as long as a week, then remove the compost and drain it off for future use. While doing so you may find some bugs which should prove to be dead by now. Feed them to the birds.
3 Meanwhile I am tearing away healthy bits of the plants, making sure there are no hiding bugs, and trying to treat them as cuttings.

Meanwhile, stop using peat based compost - they hate it and it's devastating the peat bogs.

Thanks for your suggestions and replies.
I re-read the instructions and realise that I can use the Bug Clear at any time.
I have given my fuscias a dosing. I'm not sure that they all have been infected but just want to be on the safe side without having to disturb all the roots.

When I plant out my new fuschias, I intend to place a layer of sharp sand on top of the compost. I have read that this can be effective at preventing the weevils from laying eggs in the compost.

the layer of sand /grit needs to be a good half inch to deter the little blighters. better to use a soil based compost such as a john innes type. no 2 or 3 would be best.

I also feed the grubs to the fish but if you kill them with the insecticide don't put them out for the birds/fish.

I would still knock the plants out of their pots and check for the grubs.

I use about an inch of grit on my pots to deter vine weevils and it seems to work. In the flower beds though it's a different matter. I have loads of heucheras and I watch them with an eagle eye!