Hollyhock rust

Asked August 31, 2015, 4:53 PM EDT

What do you recommend doing with hollyhocks that have either the bright orange, brown, or both colored spots on their leaves? We've tried removing the leaves and when the flowers are through blooming discard all of the stalks. They are mostly watered from soaker hoses. Should we dig up the plants and start with new ones next year? Fungicide? Thanks.

Albany County Wyoming

1 Response

Hollyhock rust if very common and sanitation is my best recommendation to manage the disease. It sounds like you are doing everything right. Keep irrigation water from wetting the foliage by using soaker hoses, remove infected leaves and stems to reduce the disease potential on next year's plants. The disease will overwinter on infected plant tissue, so removal and disposal is a good treatment. Hollyhocks are biennial plants, meaning they live for 2 years, blooming the second year. They reseed readily and new plant emerge from seed. Plants that have bloomed can be removed since they have completed their lifecycle. Even if you remove the infected plants, you will have plenty of hollyhocks next year and into the future. I generally do not recommend fungicide treatments. Thanks for the question.