Definitely not too late.

Some people cut to the ground. I always cut about 12" high. Others don't cut and sometimes end up with huge bushes I wish I had. YMMV

http://forums.gardenweb.com/forums/load/butterfly/msg0417463826103.html

Here is a link that might be useful: Butterfly Bush

Thank you so much! I really appreciate the links and I'm sorry to re-ask a question. I absolutely love my butterfly garden and my 7 year old (oops! He turned 8 today) son loves the hummingbird moths.

It's absolutely not too late. Your butterfly bushes will appreciate the "harsh" treatment. The bush will look better and bloom more. Try to cut just above an awakening bud about 8-12 inches from the ground. Once it starts growing again it'll take off and look great!

Happy hummingbird watching to you and your son!

Kim

I am in zone 7A, and I have not cut my bushes yet. I don't touch them until after the last frost date. I have learned that when I cut them, it seems to stimulate them to put on new growth, and I've lost them afterwards to late frosts. So I wait it out until mid April, then I trim them, and they bounce right back. You can even take some of the cuttings and root them for more bushes!

Sandy

Sandy, how do you root them?

I never cut mine back until sping here in CT. Since I stopped cutting them back in the fall, I haven't lost one again.

Maryann

I have had great luck putting the cuttings in a container of damp perlite and putting a cover over them to conserve moisture. You can also put them in pieces of wet foam and keep them in a container. You need to make some sort of mini greenhouse to keep the humidity high. They sprout fairly quickly.

Sandy

I'm going to prune mine to about a foot of major trunk this week and start some cuttings. I like to use rooting hormone and start them directly in potting soil in 1-gallon pots.

Just moved into a house with butterfly bushes that were not cut back in the fall. Is April 24 th too late to cut them back? There are maybe 4 green leaves total on the dead wood.

I never cut mine back in the fall. They are growing in a cold zone, in the front yard in a location where they're exposed to harsh winter winds, and not cutting them back until the Spring supposedly helps them survive the winter. I cut mine back a couple weeks ago, between 12-24 inches high, and usually back to the new shoots. I don't think it's too late in your zone to cut them back.

Sue,

you are supposed to cut back when you see the first growth coming back.

I'm cutting mine back tomorrow in Minnesota.

FYI: I usually cut mine back to about 12 inches too...I don't think the exact height matters too much

This post was edited by coolbutterfly on Wed, Apr 24, 13 at 21:28

Hello! I'm in London UK, no idea what zone (or if zones are just an American thing?). Is it too late NOW to cut them back (16th of May)?? Our gardener was supposed to have come early Spring but has left us hanging for 6 weeks before finally cancelling on our "last-chance" date. Our buddleia is enormous (probably 10 ft high, and is blocking out light and space from my favourite (& personally meaningful) plants growing near it in a very small garden. I am desperate to cut the buddleia back dramatically, but we're having one of the few warm spells we're likely to get in the UK this year. Can we still do it? Also, my husband (even less experienced than I in the garden) is convinced he can do it with a tiny little saw, but I keep telling him it looks like a power-tool job to me.... Any advice??? Many thanks!

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