If it's tall and has lots of long stems, reduce the length by a third to half - then do the proper prune in March as usual.

Ok that makes sense...….will do that thank you.

They die back in an ugly way after flowering too? Another valid reason to get the loppers out now imho

Well they are rather gawky shrubs to look at without leaves - but no worse than black elder, Sambucus nigra 'black lace' - the trunk on those always reminds me of turkey legs, and they are gawky growers, unattractive in winter. At least Buddleja produces fragrant flowers which attract butterflies.

Don't get me wrong, love buddleias. My biggest must be 15 foot tall but the mass of dead, brown flower heads when they turn is really horrible? & definitely a good reason for an early, tidying prune? It stops the prolific seeding too...

Darren8 - I deadhead my buddlejas, its one of the few times I ibother with deadheading - carefully, cos often there's little tiny flower buds and they will develop and flower before its done. Looks much better without the brown flowers as well