We had frost the first 13th of September and it has continued to frost most nights since. I started digging my dahlias today, some of them were just getting ready to bloom so it was sad to have put the time and work into them and not even get to see one bloom. I talked to a master gardener who grows dahlias about why some didn't bloom and some where so late and she thought it was just the weather this year with the heat and no rain. It would be nice to know if there were early and late season because up north the early season would be my definite choice