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Pesticide guide

Chlorothalonil

Fungicide Chlorothalonil

Description

Chlorothalonil is a broad-spectrum protectant fungicide that works by creating a protective barrier on the surface of your plants. The word 'protectant' means it prevents diseases from starting, rather than curing diseases that have already begun. The word 'broad-spectrum' means it works against many different types of fungal diseases. When you spray chlorothalonil on your plants, it forms a protective coating on the leaves, stems, and fruits that prevents fungal spores from germinating and infecting your plants. This is very effective because it stops diseases before they can cause damage. Chlorothalonil works well against a wide range of fungal diseases including early blight, late blight, leaf spots, anthracnose, and various blight diseases. It's commonly used in vegetables, fruits, and ornamental plants. One of the advantages of chlorothalonil is that it has good rainfastness, which means it sticks to the plant surface well and doesn't wash off easily in rain. This makes it very useful in areas with frequent rain or high humidity. However, it's important to know that chlorothalonil works best when applied before you see any disease symptoms - this is called preventive spraying. If you already see disease starting, you may need to use a different fungicide that can cure the disease. You should spray it every 7-10 days during the growing season when disease pressure is high. Make sure to spray both the top and bottom of leaves, as diseases often start on the underside. Always wait the required number of days (usually 7-14 days) after spraying before harvesting your crops. Always follow the label instructions and wear protective clothing when using this product.

Application rates

General

1-2 liters per hectare

Preventive

0.8-1.5 liters per hectare

Application method

Foliar spray

Target pests

Early blight Late blight Leaf spots Anthracnose Blight

Application timing

Preventive: before disease onset. Repeat every 7-10 days during disease pressure. Good rainfastness.

Safety period

7-14 days before harvest

Precautions

Wear protective equipment. Do not apply in windy conditions. Follow label instructions. Rotate with other fungicides to prevent resistance.

Crop compatibility

Vegetables Fruits Ornamental plants

Benefits

  • Broad-spectrum activity against many fungal diseases
  • Effective protectant - prevents diseases before they start
  • Good rainfastness - doesn't wash off easily
  • Suitable for vegetables, fruits, and ornamentals
  • Ideal for areas with frequent rain or high humidity
  • Well-established product with proven track record

Best for

  • Vegetable crops (tomatoes, peppers, potatoes, cucumbers)
  • Fruit trees (citrus, apples, stone fruits)
  • Ornamental plants
  • Crops in humid or rainy conditions
  • Crops requiring preventive disease protection

Usage tips

  • Apply before disease symptoms appear for best results
  • Good rainfastness means less reapplication needed
  • Repeat applications every 7-10 days during disease pressure
  • Ensure thorough coverage of both leaf surfaces
  • Ideal for humid or rainy growing conditions
  • Use as part of a preventive disease management program

Storage instructions

Store in original container in cool, dry, well-ventilated area. Keep container tightly closed. Store away from food, feed, and water sources.

Mixing compatibility

Compatible with most fungicides and insecticides. Do not mix with alkaline products. Check compatibility before tank mixing.