Removing ground debris helps control the fungus. If a Garden is mulched, the mulch should be removed and replaced each spring. Chemical control may be necessary if rust reoccurs. Sulfur, applied as a dust or liquid spray, is effective and must be aimed at the underside of lower leaves. Using sulfur, providing good air circulation and avoiding overhead watering, especially in the evening, will reduce the severity of hollyhock rust.
Some plant varieties are rust resistant.
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