Copper sulfate is a versatile fungicide, algaecide, and bactericide used for generations in agriculture, horticulture, and water treatment. Its blue crystals release copper ions upon contact with water to inhibit the germination of fungal spores and eliminate algae—a multi-site action to which no cases of resistance have been reported. Approved for use in organic agriculture by the Quebec Phytosanitary Warning Network, it is suitable for both backyard gardeners and farmers seeking an approved solution for organic farming.

Main uses

• Foliar fungicide — preventative treatment against powdery mildew, scab, rust and blight of fruit trees, potatoes, cucurbits and small fruits; apply at 2–8 g/L of water before spore germination.
• Algaecide for ponds and swimming pools — eliminates green algae and bad odors; dissolve in a plastic container then pour around the perimeter at 1 tbsp per 4,000 L of water (pH 7.2–7.6, water ≥ 15 °C).
• Soil and moss treatment — controls moss and fungi on outdoor surfaces, walkways and roofs; concentration of 20–50 g/L for targeted burning effect.
• Organic farming — one of the only mineral fungicides authorized against downy mildew in certified organic management; check with your certification body before use.
• Application safety — always use a plastic container (never galvanized metal); wear gloves and goggles; avoid spillage near waterways, as the product is toxic to aquatic organisms.

Specifications