I wonder if anyone can tell me the best way to propagate this compact variety. It's just starting to flower, but I think the spread will be less than last year. The problem is that the new shoots are tiny and only seem to sprout from last year's twigs, which are brittle and snap easily. The middle of the plant is now very congested but I am reluctant to try and divide the root system in case I kill the thing.

Last Autumn I took woody cuttings and, although some are still in leaf, they show no sign of rooting.

Any advice appreciated.