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Is there such thing as successful “organic” or “natural” treatment against Anthracnose ?
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Yes it is called Soil Health. Something that cannot be accomplished with colonial farm practices.
When I have bought new Zills Mangos they almost always show signs of some sort of fungal disease. I use a homemade foliar spray made from a fermented milk, Bokashi soldier fly leachate, biodynamic compost tea a humus tea and a cinch weed yeast tea all mixed and sprayed weekly. I’ve noticed it can take up to a year before all signs of disease disappear.