[diggleken]

It may be both sods and clothing - clout is certainly archaic old english for cloth remnants to piece or repair workclothes. Possibly more up north here.
I have always understood it from old yorkshire and lancashire millworker and farming folk to mean dont think you can get rid of your winter apparel or clothes until youre quite sure the seasons have warmed with spring proper.
Oh, forgot to add, May meaning hawthorn, as said.
Cheers
Ken