To be honest hawkie, there are no laws for bonfires in gardens - I took this issue up with our local councillor recently over bonfires in allotments that back onto my garden. The allotment owners seem to think it is their right to have a bonfire in the middle of the day - bearing in mind there is a junior school backing onto them aswell.
As a rule, my husband normally waits until after 6. p.m and makes sure nobody still has washing out and then he lights one then.
I hope this helps.