Posted: 25/11/2012 at 17:34
If sawfly have been a problem this year, you may find eggs and chrysalises have dropped into the surrounding soil ready to hatch next year. Carefully clear away any fallen leaves and gently dig over the soil surrounding your bush, this should destroy most eggs and chrysalises, you don't need to dig too deep they'll be near the surface.
If you decide to spray next year it's more effective to spray before the first sign, in about April.