I think I would start them inside (an unheated greenhouse) although I also have dahlias still in the ground. Those overwintered outside have no visible signs of growth (thankfully) as our last frost date can be as late as 1st week in June. In 6 weeks or so they will be sturdy plants to go outside.

thanks campanula
my last frost date is the last week in may.
i'd prefer to start them outdoors as my growing space is limited but to youâÂÂre probably right...i should start the indoors