Hollyhock rust – Puccinia malvacearum
Pathogen: Puccinia malvacearum
Hosts: Alcea, Althaea, Lavatera, and Malva.
Symptoms: Small brown spots develop on the underside of foliage. Raised, bright yellow or orange pustules are visible on the upper leaf surface. When disease is severe large portions of the foliage are killed.
Spread: Spores can over winter on diseased plant tissues infecting new foliage the following year. Spores are also produced on susceptible weeds these can subsequently infect and cause disease on hollyhocks. Spores are wind dispersed.
Management: Disease control on seedlings is especially important. Fungicide applications at regular intervals are necessary when disease is severe. Plants should be cut back as soon as flowering is done. Plant debris should be removed and destroyed, it should not be composted. Several weeds (in the mallow family) are also susceptible; these weeds should be controlled to limit inoculum in the growing area.



Other Documents in this Series
You Might Also Be Interested In
-
TelFarm Newsletter Summer 2025
Published on June 20, 2025
-
2023 Farm Business Analysis Report
Published on February 13, 2025
-
Tax Estimation Form 2024
Published on November 1, 2024
-
Depreciation Notes 2024
Published on November 1, 2024
-
Tax Tips 2024
Published on November 1, 2024
-
TelFarm Newsletter Fall 2024
Published on October 15, 2024
Accessibility Questions:
For questions about accessibility and/or if you need additional accommodations for a specific document, please send an email to ANR Communications & Marketing at anrcommunications@anr.msu.edu.