i bought a couple of 'blue chip' dwarf buddleias last year but the planting instructions didn't say whether to prune or not to maintain their shape and promote flowers.
I've just pruned my dwarf buddleias for the 3rd year in a row - definitely recommended. the first year I took about half the growth off.
I've had my Buddlielas for several years and both are in large pots. I prune mine every spring by a least a half. Pruning them hard helps promote flowers and they grow a nice shape. I scrape some of the compost off the top and top dress them with new, and I keep them fed and water well all through the summer. Last summer they were covered in flowers and of course butterflies.
thanks for that! i've no problem with cutting back my normal buddleias but was shy of doing the same to the dwarf variety!