The most common way to use copper on plants is by spraying a copper-based fungicide. This helps control various fungal and bacterial diseases.
Here's a breakdown of how to use copper products on plants:
1. Identify the Need:
- Disease Identification: First, accurately identify the fungal or bacterial disease affecting your plants. Copper is effective against common issues like blight, leaf spot, and downy mildew.
- Prevention vs. Treatment: Copper can be used both preventatively and as a treatment. Preventative applications are best applied before disease symptoms appear, especially in conditions favorable for fungal growth (high humidity, frequent rain).
2. Choose the Right Copper Product:
- Copper Sulfate: A traditional form, often requiring mixing with lime to prevent plant damage (Bordeaux mixture). This can be more complex to prepare.
- Copper Octanoate (Copper Soap): Generally considered safer for plants, this is often available as a ready-to-use spray or a concentrate.
- Copper Ammonium Carbonate: Another readily available option.
3. Mixing and Application:
- Ready-to-Use Sprays: If you have a ready-to-use copper fungicide, simply shake well and spray directly onto the affected plant parts.
- Concentrates: If you have a liquid concentrate, carefully follow the product label instructions for dilution. A typical ratio is 1-2 tablespoons per gallon of water, but always defer to the manufacturer's instructions. Using too much copper can damage your plants.
- Application Technique:
- Even Coverage: Spray plants thoroughly, ensuring all surfaces (tops and bottoms of leaves, stems, and fruit) are covered.
- Avoid Runoff: Don't spray so much that the solution drips off the plant.
- Timing: Apply in the early morning or late evening to avoid leaf burn from the sun. Avoid spraying when rain is expected within 24 hours.
4. Safety Precautions:
- Protective Gear: Wear gloves, eye protection, and a mask when mixing and spraying copper fungicides.
- Avoid Inhalation: Avoid breathing in the spray.
- Wash Thoroughly: Wash your hands and any exposed skin after application.
- Keep Away from Children and Pets: Store copper products out of reach of children and pets.
5. Frequency of Application:
- Follow Label Instructions: The frequency of application depends on the specific product and the severity of the disease. Generally, reapply every 7-14 days, or after heavy rain.
Important Considerations:
- Plant Sensitivity: Some plants are more sensitive to copper than others. Test the solution on a small area of the plant before applying it to the entire plant.
- Soil Accumulation: Copper can build up in the soil over time, potentially harming beneficial soil organisms. Use copper products judiciously.
- Organic Gardening: If you are an organic gardener, ensure that the copper product you choose is approved for organic use.
By following these guidelines, you can effectively use copper on plants to control fungal and bacterial diseases while minimizing potential risks.
