Well, I have no clue why Floridata (usually reliable sourse) made such statement, but here is a quote from not less respected sourse, Missouri Botanical Garden, 'If bloom is not a concern, stems may be cut back hard in early spring each year to a framework to induce growth of vigorous new shoots with slightly larger than normal leaves. Such hard annual prunings will control size, but most likely at the expense of profuse flowering. Hard pruning is more often done on the purple-leaved cultivars.' My personal experience is in full compliance with above statement. I guess, 'most likely' are a key words. Here is a link that might be useful: Kemper's Cotinus page

I'm not a buddleia expert, but, I think the butterfly bush pruning rules apply mainly to cold, continental type climates, where a late freeze in May could stunt its ability to successfully make new growth for the duration of the growing season. I don't think it gets that cold in London, does it? I'm under the impression that all of Britain has a fairly mild climate, thanks to the Gulf Stream. I live in a mild climate (except for the hot, humid summers) and mine hold most of their leaves all winter long - I prune mine to about 2 ft. - 3 ft. tall in early spring. If yours has grown 10 ft. tall, then you must be getting enough heat for good growth. I say, go ahead and prune it, it'll probably do it good, make it bloom more, which is what you really want. It's your garden, and if it's blocking much-needed UK light, then it needs a trim! Sherry

I would think you could just prune it back a little bit to stimulate fuller growth without sacraficing size much. Even a more drastic pruning won't necessarily result in a smaller bush. Every other year or so I hard prune my Abelia and they return the same size they were, just fuller. The same seems to be true of butterfly bushes, but I don't have any mature ones to say for sure. Somehow the one I planted for my mother sprang to full size in two years while mine are still half the size. She has better sun, I blame it on that. Anyways, I think pruning it by up to half will result in a prettier bush with more blooms that I doubt will be any smaller. At the same time, it won't hurt it to leave it alone for another year either. -Ais.

I just did a quick search to find this: http://www.gardenseeker.com/pruning/pruning_buddleja_buddleia.htm which seems to indicate that earlier is better and March should do fine. I'd do it now because you're a zone warmer than me and I've already got willow budding up here. I didn't search for the fertilizer for you. :p I just wanted to warn you against fertilizing too early! you don't want to send it into a growth spurt when it should still lay dormant in this colder (freeze-prone) weather.