Overwintering hardy perennial seedlings

borgadr

I was wondering what the general consensus is for overwintering potted seedlings of hardy perennials?
-  Just leave them outside to toughen them up?
-  Cosset them in the greenhouse over winter to extend the autumn growing season and get them off to an early start before hardening them off in spring?

In my case, it's erigeron seedlings (very young, sown last month) and eryngium young plants (sown early spring, for planting out next year).

JennyJ

Outside but in a sheltered place (eg up against the house wall under the eaves) to keep the worst of the winter rain off, assuming you get any! They might do what perennials do, die back over winter and grow from below soil level in spring. If that would worry you, you could keep them in a cold greenhouse but make sure they don't completely dry out. Or maybe half-and-half, and compare the results.

borgadr

@JennyJ I do like that half and half idea. I think I'll give it a try 

JennyJ

Let us know how you get on. Experiments are always interesting!

nutcutlet

If growing well and filling their pots mine are outside. If tiny and recently potted they're in an unheated GH