When my rock rose has finished flowering what should I do, or do I have to leave cutting back to the spring?
If we're talking Helianthemums, I don't do a thing to mine. Just leave them to their own devices and they put on a stunning display every year. Mine are planted in a very well drained bed behind a south facing drystone wall and they trail all down the front. If you are limited for space, I would say autumn or early spring for cutting back.
Thanks I will leave them alone