Fungus and Disease Control
Biological fungicides Beneficial microbes protect plants from soil-borne pathogens, like pythium, botrytis, as well as air borne pathogens like fine blight, powdery mildew, and more. Unlike mineral-based fungicides, they supplement rather than harm biological life in soil.
Botanical insecticides/fungicides Made from plants with pesticide qualities. These materials, while safer to the user and the environment than chemical pest controls, are very strong and should be used as a last resort. Used inappropriately, these stronger botanicals, like rotenone, pyrethrin and sabadilla, can cause more trouble than they relieve by upsetting your biological balance and triggering secondary pest outbreaks. For severe situations they can be used on a temporary basis. Use respirator, protective clothing, follow label instructions exactly.
Neem Oil Best used as a preventative or in low disease pressure situations for fungus problems. Use to control diseases such as powdery mildew, anthracnose, botrytis, rust, leaf spot, and flower blight.
Oil products Used as dormant oils, growing-season sprays or spray adjuvants for smothering pests such as overwintering scales, mites, aphids, and peach twig borer. May be unnecessary for small scale users unless experience shows a serious problem with these pests. Many orchards do well and have never been sprayed with oils. In commercial applications or serious pest outbreaks, the use of oils may be necessary.
Mineral fungicides Generally considered acceptable for organic production, but should be used as a last resort. Other options are highly preferable to mineral-based fungicides because they do not harm beneficial microbial populations and leave soil’s “immune system” intact. If you do use mineral fungicides, follow the label to the letter. As some people are sensitive to sulfur and copper based materials, we recommend the use of respirator masks and protective clothing. Note that copper is alkaline with a tendency to accumulate in the soil, so minimize its use. Sulfur, on the other hand, is acidic and is assimilated by the plant and soil as a nutrient.
Copper fungicides The strongest and most broad-spectrum fungus controls we offer. Use only when other techniques have failed. Copper can be detrimental to plants and soil when applied in rates above the recommended amounts. Often used in the dormant season. Read the label!
Sulfur fungicides & miticides Sulfur is broad-spectrum with little detrimental environmental effects. Can be irritating to the eyes, ears, and nose during application, use protective clothing and masks. Used for the control of powdery mildew on grapes and other crops and is effective against most species of pest mites, brown rot, rust, and scab. Often used in the dormant season.
Note to Certified Organic Farmers: While we do our best to stay current with product OMRI listings, be sure to check with your certifying organization for a current list of approved (or banned) products.
Check out our video on Powdery Mildew Control:
Find the solutions you need in our Pest Control Solution Chart:
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