Marty wrote
Probably a silly question but how do you guys decide when it's safe to
assume there'll be no more frost?

Old gardeners used to say it's OK after the Chelsea Flower Show (end of May)
and for me that usually works fine but a few years ago we got a Grass Frost
on our exposed allotment on the 9th June which didn't do my tender plants
much good. No sign of that frost at home in a built up area, so it depends
where you're gardening.

--
Regards
Bob Hobden
17mls W. of London.UK