Recognise hollyhock rust
Recognise hollyhock rust
17th May 2020
Where hollyhocks do seed themseves in the same position year after year, you are unlikely to be able to avoid holyhock rust - plants will set seed in the summer and often survive for another year or two as short-lived perennials, and they transmit the disease spores to the young foliage of the next generation. Undersides of the leaves are dotted with bright yellow or orange-red rust spots with yellow pinpricks on the upper surface, and eventually the leaves fall. You can reduce transmission by pulling up all the old plants as soon as the seeds have set and scattered, treating them as biennials.