My logic is this... We haven't had frost in over a week and no frost is in the forecast for the next week. Lots of perennials which usually show up with warm soil temps have broken ground - Echs, Asclepias, Buddleias, etc. so the ground has warmed-up. Should be OK, right?!?

I have planted some of mine in zone 5b as part of an experiement already. But I usually wait till 5.15 or so to plant out and even so, I will need to cover them a few nights if it gets too chilly. Mother nature is always up to tricks with late season frosts!

Keriann~

We have not had a frost in several weeks in the 6/7 section of Massachusetts, and I still have to worry about having frost blankets in case a frost crops up in May. Indeed, I getting the frost blankets ready for tomorrow night when the temp is going down to at least 36, maybe lower. Since I am 'risking it' here by planting plants, I wonder if you are risking more because you are in a colder zone and you are planting tubers.

I am all for starting earlier than conventional wisdom, but given all the factors, including the ground temp and the potential for more frost, I would think you would have better putting them in pots for a couple of weeks.

That said, Sid's Dahlias in Nova Scotia has some wisdom about spring frosts on its web page:

"A late spring frost will kill young sprouts, but they will usually sprout again."

Hoping to get some nice Dahlia tubers this weekend from the Nova Scotia Dahlia Society annual sale. Goodies are being sold early Saturday and I am looking for some medium sized orange, peach, and lilac colours. Looking forward to expanding my 'repertoire'!!