On Monday, 8 February 2016 21:41:00 UTC, Vir Campestris wrote:
On 08/02/2016 21:03, Mathew Newton wrote:
I may well give another treatment at the end of summer, following hatching of eggs laid by those I've missed, to hopefully remove this factor from the equation for next winter...

Leatherjackets are the larvae of craneflies. They don't lay eggs
themselves - they have to emerge as adults, and then the adults lay
eggs.

That's what I meant - I'll retreat in Sep/Oct when the eggs laid by any crane flies (there are bound to be some) start to hatch.

If you can keep the adults off somehow you won't have a problem next
year.

We used to have a cat that would chase and eat them.... The one we've got now is too lazy for that sort of thing though so it might be down to me (to chase at least!).

Mathew