I have found over the years that the last frosts are very often in that
period 3 days either side of the Last full Moon in May (if you have clear
sky's), and the first frosts also come in the same 6 day period from end of
Sept.
It's not 100% but works more often than not.


--
David Hill
Abacus Nurseries
www.abacus-nurseries.co.uk