Hi Roger, many people cut their buddleia almost to the ground each March, I've always found them impossible to damage. I'm assuming it's a common buddleia (davidii?). When treated this way, they can look fantastic and stay as a very manageable shrub. Hope this helps:-)

Buddleia is one of the toughest shrubs, and can take very hard pruning. You can cut it right back to about a foot - around March time.

I used to cut them off just a couple of inches above the ground in spring and they'd still grow over 6 feet in a year. I've found that they're unkillable. Prune as you like Roger - you won't do any harm, except possibly cut off some flower spikes if you prune in summer.

I once left my pruning very very late April, all that happened is it flowered late lol:-)

I agree with everyone else and I also had patio buddlia
this year for the 1st time and they were superb with lots of flowers and a nice low bushy shape.

I must be lucky then, I have managed to kill 3 so far this last couple of years, just by pruning. Am going to try to kill all the others this coming year.

Good grief Owdboggy, it must be some gift you have lol. I would have had you sort out my rhus typhina if i had but known:-))

Believe it or not, when we moved here there was a big one of those monstrosities in the garden. We dug it out and it has never reappeared. Mind, if I could do it to Symphoricarpus I would be really pleased!
The Buddleja I am trying to remove are all self seeded poor quality wildings by the way.

LOL Owdboggy! I wish I had your touch! How are you on bracken?

I have snowberry too Ob it snuck in from next door years ago, shame your murderous technique doesn't work with it:-)

I find with my buddleia davidii I cut them right back to about 6" but in 2 stages - 1/2 way in the autumn and then the rest comes off in March and I still end up with a wide/tall 6-8ft shrub by July.

Assuming you have B. davidii and not globosa or alternifolia, prune in late March/early April, depending on how cold it is at the time. Cut down to within an inch of the previous year's growth - cutting into older wood can mean the plant doesn't recover and dies, although you might get away with it. Pruning correctly every year usually means you end up removing a good six feet or more of growth from the previous year.