Overgrown Rhodanthemum Pruning?
This Rhodanthemum was accidentally left behind at my old house - it’s now been rescued but is significantly overgrown... the RHS website says not to prune, but surely it needs a good cut back? But how far? And when’s the best time?
edited June 2021
... well, I'm not as cautious as the RHS, as I have no reputation to uphold, so here's a different answer..
.. I dug up mine in freezing late winter, to move to a different part of the garden, which meant it was virtually bare rooted, as they don't come up with much rootball..
..I pruned it back quite hard, but left a few bits of foliage on here and there.. some dieback has occurred which I've cut out, but the rest is recovering well.. and as you can see, it appears to reshoot from quite low down into older wood..
.. so I would say cut back by half if you want, even more, and now would be a good time I should think...
East Anglia, England