Caryopteris divaricata 'Blue Butterflies' hardiness
What's the possibility of this one overwintering in zone 4-5? I've done some checking and various sites list it as hardy mainly in zone 5-6, but a couple have said zone 4. It's been a really long time since we've had a typical MN winter with subzero temps for any length of time, but I suppose that could happen again.
Should I take a chance?