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How to Manage Pests

Pesticide Information

Bordeaux mixture

Type

Inorganic fungicide.

Plant uses

Mostly for dormant treatment of fruit and nut trees; registered specifically for tomatoes, strawberries, apples, peaches, and grapes; young leaves of trees may be burned.

Pests controlled

Fungal diseases of fruit and nut trees, especially brown rot, shot hole, peach leaf curl, and fire blight. Some insect species may be repelled and some bacterial diseases may be controlled.

Potential period of activity after treatment

Several weeks to months if not washed off; can weather rainfall in winter.

Precautions and safety equipment

Bordeaux mixtures may injure young plants or young leaf tissue any time and can injure people. Minimize your exposure to pesticides. A dust and mist filtering respirator is required during mixing. Unless otherwise stated on the label, wear rubber or neoprene gloves and boots, eye protection that covers the brows and temples, and long pants, a long-sleeved shirt, and a hat that can be washed after each use. Corrosive to equipment.

Active ingredient

Copper sulfate and hydrated lime (calcium hydroxide). Equal parts copper sulfate and hydrated lime are mixed with water, commonly at a ratio of 8-8-100 gallons water or 12-12-100.

Application tips

Bordeaux mixtures are applied primarily during the dormant season. Avoid use on actively growing tissue. It is a protectant and must be applied before infection occurs. Thorough coverage of surfaces is essential. Treated plants will look blue, so the spray is not commonly used on ornamentals.

See the Bordeaux Mixture Pest Note for more information.

Always check the label before purchasing or applying a pesticide product for a specific pest on a specific plant to be sure it can be applied. Follow label directions precisely.

WARNING ON THE USE OF CHEMICALS