Plant diseases caused by fungal pathogens are very common in home gardens in the Pacific Northwest, particularly west of the Cascade Mountains. Spring rains combine with warm temperatures and tender new plant growth to create ideal conditions for fungi to thrive and spread. Common fungal diseases seen in home gardens include powdery mildew, downy mildews, rusts, and late blight. Fortunately, there are many products available to home gardeners for managing diseases caused by fungal pathogens on plants. This fact sheet describes organic fungicides and provides information on:
• which organic fungicides are legal and available to home gardeners,
• how effective these organic fungicides are, and
• whether the products have unintended effects on people or the surrounding environment
More information is available on this free, downloadable fact sheet: http://cru.cahe.wsu.edu/CEPublications/FS128E/FS128E.pdf
Submitted by: Linda Chalker-Scott, May 15, 2015
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