I've just strimmed down some waste ground/overgrown edges for the owner
of some local lock-ups garages, then I went over it with sodium chlorate
weedkiller, to stop any new growth.
He has paid me to do it [1], and I said I'd be back in 2 or 3 weeks to
strim down any new growth, and re-apply some weedkiller to those spots.

How long should i leave it to check for new growth - is 3 weeks enough?
And, probably the same answer, when should I go back and re-apply?

Thanks
Alan.

[1] I now realise why he agreed so quickly for me to do it for £55 inc.
weedkiller - I've spent 3 hours there already, need 1 more hour to clean
up, as well as spending £12 on 3kg of Sod. Chlorate.
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