Cast n'er a clout 'til May be out

Right on, mav. Presumably this is an entirely English expression, dependent on our particularly indiosyncratic climate? Or does it occur elsewhere in the world?

Incidentally, there is a deal of confusion over the correct interpretation of the above old saw.
Does it mean (as I believe), "wait until the May Tree is flowering (i.e., "out") before divesting yourself of warm clothing;"
OR - does it mean (as many would aver), "Do not remove warm clothing before June 1st."