Magnesium deficiency
Magnesium deficiency in cannabis plants can have serious consequences for plant growth and health. Magnesium is an important component of chlorophyll and plays a key role in photosynthesis and enzyme activity. Here's a detailed overview of magnesium deficiency in cannabis, including symptoms, causes, and treatment options:
Symptoms of magnesium deficiency
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Leaf discoloration
- Interveinal chlorosis: Magnesium deficiency often manifests as a yellowish discoloration between the leaf veins, while the leaf veins themselves remain green. This typically begins in the older leaves.
- Leaf changes: In advanced stages, affected leaves may develop brown or necrotic spots that spread inward from the leaf margins.
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Leaf structure
- Leaf necrosis: Affected leaves may exhibit brown, necrotic areas. The leaf edges may also become dry and brittle.
- Leaf distortion: The leaves may curl or twist, and the plant may appear smaller overall.
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Growth disorders
- Slowed growth: Magnesium deficiency can slow the overall growth of the plant and impair the formation of new shoots and leaves.
- Flowering problems: Severe magnesium deficiency can impair flower development and reduce harvest quality.
Causes of magnesium deficiency
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pH problems
- Unfavorable pH: Magnesium is most readily available in the soil or medium at a pH of approximately 6.0 to 7.0. At pH values that are too high (alkaline) or too low (acidic), magnesium becomes less available.
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nutrient imbalance
- Overfertilization: An excess of calcium or potassium can impair the absorption of magnesium.
- Lack of supply: A lack of magnesium in the soil or medium can lead to symptoms of deficiency.
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Soil structure
- Soil: Very light or permeable soils may contain lower amounts of magnesium. Highly acidic or alkaline soils can also impair magnesium availability.
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Water quality
- Inadequate quality: Water that is low in magnesium or has been heavily filtered can also lead to a deficiency.
Treatment and prevention of magnesium deficiency
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Magnesium supplementation
- Fertilizer: Use fertilizers that contain magnesium. Many commercial fertilizers contain magnesium in the form of magnesium sulfate (Epsom salt) or magnesium chloride.
- Foliar fertilizer: A quick solution can be the application of magnesium-containing foliar fertilizers, which are applied directly to the leaves. This allows for immediate absorption by the leaves.
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pH adjustment
- Check pH: Check the pH of your soil or medium regularly. The ideal range is 6.0 to 7.0 for soil and 5.5 to 6.5 for hydroponics.
- pH correction: If the pH value is outside the optimal range, use pH reducers or increasers to adjust the value.
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Nutrient management
- Avoid over-fertilization: Avoid over-fertilization and ensure that the plant receives a balanced supply of nutrients.
- Magnesium-containing products: Use special nutritional solutions or supplements containing magnesium to compensate for the deficiency.
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Soil and water analysis
- Soil analysis: Conduct regular soil analyses to ensure that magnesium and other essential nutrients are present in the correct proportions.
- Water quality: Check the water quality for possible nutrient deficiencies or excesses.
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Hygiene and care
- Cleanliness: Keep the growing environment clean and avoid damage to the plants that could impair nutrient uptake.
- Water absorption: Ensure consistent and adequate watering to promote nutrient absorption.
Summary
Magnesium deficiency in cannabis manifests itself as yellowish discoloration between the leaf veins (interveinal chlorosis), brown spots, and slowed growth. The main causes are an unfavorable pH level, nutrient imbalance, inadequate soil structure, and inadequate water quality. Treatment includes supplementing magnesium with appropriate fertilizers, adjusting the pH level, avoiding overfertilization, regular soil and water analysis, and good cultivation hygiene. Through these measures, you can effectively prevent and treat magnesium deficiency.