Posted: 18/09/2013 at 20:12
Burncoose list it as on the tender side, so I have never tried it this far north, even though I have had a lot of different buddlejas over the years.
I seem to be ok with davidii cultivars- pink, white, nanho blue, dartmoor, harlequin (weak), and globosa and x weyerana, and alternifolia.
I found B. fallowiana pretty, but weak and I lost it.
The butterflies seem to prefer the wild pale purple davidii type, in preference to the other colours.