Copper Fungicides for Tomatoes

copper tomato fungicides

Copper fungicides have long been relief upon by both organic and conventional tomato growers to control many of the diseases affecting these plants. Not only are copper fungicides safer to use than many other fungicides on the market, they are also effective, and can be used up to a day before harvest.

Copper fungicides work as a result of the absorption of the copper ions by invading bacterium, causing the bacteria to become denatured. While copper alone is very soluble in water and therefor would be toxic to tomato plants, the copper hydroxide (made by combining copper with lime) used in copper fungicides is not water soluble, preventing the fungicide from damaging any of the plant material.

Tomato Copper Fungicide Recommendations

  • Bonide Liquid Copper Fungicide can be used with both hose-end sprayers and hand-pump sprayers. Diseased plants should be sprayed thoroughly, and reapplied if any signs of disease persist 7-14 days after the initial spray. While it’s perfectly safe to reapply this fungicide sooner if the weather has been particularly rainy, Bonide Liquid Copper fungicide is very resistant to weather, and such reapplication may not even be necessary. In addition, it can be mixed with a “sticker” for use as a dormant fungicide even when no signs of disease are present on the tomato plants. Bonide Liquid Copper fungicide is safe for use on indoor plants, and can be used to treat and prevent diseases on a large variety plants, flowers, and trees.

  • Bonide Copper Spray or Dust can be applied by two different means. Used as a dust, it should be applied so as to create a film covering both the top and bottom of the tomato plant’s leaves. Used as a spray, it should first be made into a paste by adding a small amount of water, then, after straining the paste, mixed with the desired quantity of water to create a spray of adequate strength for the needs of your tomato plants. Bonide Copper Spray or Dust is commonly referred to as Bordeaux mix, which is quite a compliment considering the fact that Bordeaux was the name of the original copper fungicides invented over a hundred years ago.

  • Bonide Dragoon Dust with Copper is a unique blend of Copper, Carbaryl, and Rotenon specifically designed to act as a dual-purpose fungicide and pesticide in vegetable gardens. Like Bonide Copper Spray or Dust, Bonide Dragoon Dust with Copper can be used as either a dust or a spray. However you choose to use it, rest assured that your tomato plants will retain their natural beauty – Bonide Dragoon Dust with Copper is tinted green to blend in with the very foliage it protects. This fungicide can also be used to both prevent insects and diseases entirely, as well as to control them after they have appeared.

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