My understanding is that they are hardy to Zone 3 - which would just put us inside their zone. We have them all over town here - darned near grow like weeds around here (not that I would complain because I love the smell of them).
I have been told by somebody who knows more about plants than I do that this is more likely a variety of dwarf lilac than a butterfly bush. That might explain why it does well in this climate.
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Date: 2012-06-03 10:02 pm (UTC)no subject
Date: 2012-06-03 10:08 pm (UTC)no subject
Date: 2012-06-04 02:11 am (UTC)no subject
Date: 2012-06-04 08:21 pm (UTC)no subject
Date: 2012-06-05 09:32 am (UTC)A pity, since in my experience (from growing up in Maryland, where Buddleia does just fine) lilac doesn't attract butterflies nearly as strongly.