Posted on Nov 28, 2023 at 4:00 pm by Emily Q
Bordeaux mixture, a mixture based on copper sulfate and lime, is a traditional and effective fungicide treatment for protecting your fruit trees against diseases.
It is particularly effective against apple scab, peach leaf curl, canker, and brown rot. To make the most of it, it is essential to know when to use it and how to prepare and apply it properly.
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Key moments for using Bordeaux mixture on your fruit trees
- Early winter: After the leaves have fallen, a preventive application can be made to protect wounds caused by pruning or natural injuries.
- During winter: A second application can be made during the dormant period to strengthen protection against fungal infections.
- Early spring: Before the buds start to swell, spray again to prevent the development of diseases when the trees are most vulnerable.
Note that excessive use of Bordeaux mixture can harm biodiversity and pollute the soil and water. Therefore, it should be used sparingly and only when necessary.
Preparing Bordeaux mixture: ingredients and necessary equipment
To prepare homemade Bordeaux mixture, you will need the following ingredients:
- 100 g of copper sulfate (available at garden centers)
- 150 g of hydrated lime
- 10 liters of water
As for equipment, you will need a bucket, a stirrer (a stick will do), a sieve or fine strainer, and a sprayer suitable for phytosanitary products.
Steps to properly prepare and apply Bordeaux mixture
- Dilute the copper sulfate: In a bucket containing 5 liters of water, dissolve 100 g of copper sulfate, stirring well with a stirrer.
- Prepare the hydrated lime: In another bucket, mix 150 g of hydrated lime with 5 liters of water. Stir until a homogeneous consistency is obtained.
- Pour the lime into the copper sulfate: Slowly pour the lime-based mixture into the bucket containing the copper sulfate while stirring constantly. This will give you a ready-to-use Bordeaux mixture.
- Filter the preparation: Before filling your sprayer, remember to filter the mixture to avoid deposits and nozzle clogging.
- Apply to fruit trees: Spray the Bordeaux mixture evenly on the branches, trunk, and pruning wounds of your fruit trees, making sure to cover all surfaces. Avoid treating during rainy or freezing periods to prevent the mixture from being washed away.
Precautions for successful treatment
To ensure the effectiveness of the treatment and protect the environment, follow these recommendations:
- Respect the indicated doses to avoid excessive copper accumulation in the soil.
- Do not use utensils made of aluminum or galvanized iron during preparation, as they can react with copper sulfate and render the treatment ineffective.
- Wear gloves, goggles, and a mask when handling the products and during treatment to protect yourself from skin or respiratory irritations.
By following these tips, you will be able to fully enjoy the benefits of Bordeaux mixture in protecting your fruit trees from diseases and ensuring a bountiful and healthy harvest.