Evaluation of Fungicides for Hop Powdery Mildew, Study 1, Granger, Washington, 2025

Powdery mildew of hop is caused by Podosphaera macularis. This disease affects all green tissue of the hop plant, forming white colonies of mycelia and conidia. Infection of the inflorescence, or cones, can lead to discoloration, shatter, and damage to crop yield and quality. This report communicates efficacy data of various fungicides against powdery mildew. This trial was conducted on the hop ( Humulus lupulus) cultivar ‘Galena’ during the spring and summer of 2025, near Granger, WA. Results from this trial will help producers develop more effective management approaches for the disease.