You can drastically reduce their size, for a while, by firm pruning. I've done it & providing you dont do it much later than early August, to allow it to settle before the colder weather, it should cope quite well. I'd always take cuttings & check they've taken first before I got the pruning saw out though. So that would mean next year now to do a really hard prune.
Yours is such a feature & obviously very happy though I'd be inclined to let it be. BTW bees usually love them too. J.