Cutting back red valerian
Q: There’s a mass of red valerian growing in our old flint stone boundary wall. It looks pretty, but I wonder what I should do with it now that flowering is over.
A: Cut red valerian (Centranthus ruber) very hard back, Mrs Deakins, and look forward to a second crop of flowers within a few weeks. In future and to prevent over-copious self-seeding, cut it back as soon as the flowers have fallen in mid to late June. With repeated trimming, you can get several flushes between May and October.