A guide to Nutrient Deficiencies – Zinc

Zinc deficiency in horticulture refers to a condition where plants do not receive an adequate supply of the essential micronutrient zinc (Zn).

Zinc is vital for plant growth and development as it plays a crucial role in various biochemical and physiological processes. When plants lack sufficient zinc, they can exhibit a range of symptoms, which can ultimately impact their overall health and productivity.

What are the symptoms of Zinc Deficiency?

• Interveinal Chlorosis: One of the most common symptoms of zinc deficiency is interveinal chlorosis, where the tissue between the veins of the leaves turns yellow or white while the veins remain green. This is often seen on the younger leaves of the plant.
• Stunted Growth: Zinc deficiency can lead to reduced plant growth, including shorter stems and smaller leaves.
• Leaf Deformation: Leaves may become distorted or misshapen, with irregular margins and a puckered appearance.
• Delayed Flowering and Fruit Development: Plants may take longer to produce flowers and fruits, and when they do, the yield may be reduced, and the quality compromised.
• Reduced Root Development: Zinc deficiency can also affect root growth and development, leading to weaker and less extensive root systems.

Zinc Deficiency in Poinsettia

What are the impacts of Zinc Deficiency?

• Reduced Crop Yield: Zinc deficiency can significantly reduce the yield of horticultural crops, including fruits, vegetables, and ornamental plants.
• Lower Quality Produce: Fruits and vegetables produced by zinc-deficient plants may be smaller, have poor coloration, and exhibit taste and texture issues.
• Increased Susceptibility to Disease: Zinc-deficient plants are often more susceptible to various diseases and pests due to their weakened state.
• Long-Term Soil Degradation: Continuous zinc deficiency in horticultural crops can lead to a depletion of zinc in the soil, making it challenging to grow healthy plants in the future.

Zinc Deficiency in Pelargonium

How should you manage Zinc Deficiency?

• Soil Testing: Conduct soil tests to assess the zinc content in the soil. This helps determine the severity of the deficiency and the appropriate corrective measures.
• Fertilisation: Correct zinc deficiency by applying zinc-containing fertilisers, such as zinc sulfate or zinc chelates, to the soil. The application rate and method should be based on soil test results and crop requirements.
• Foliar Sprays: In cases of severe deficiency, foliar sprays containing zinc can provide a quick remedy. These sprays are absorbed through the leaves and can help alleviate symptoms temporarily.
• pH Adjustment: Zinc availability in the soil is influenced by soil pH. Ensure that the soil pH is within the appropriate range for zinc uptake, which is typically between 6 and 7.
• Crop Rotation: Rotate crops to prevent the continuous depletion of zinc in the soil and to reduce the risk of recurring deficiencies.
• Organic Matter Addition: Incorporate organic matter into the soil, as it can improve zinc availability by enhancing soil structure and microbial activity.
• Avoid Overfertilisation: While correcting zinc deficiency is essential, overapplication of zinc can lead to toxicity issues. Follow recommended application rates to avoid excessive zinc in the soil.

Zinc Deficiency in Poinsettia

It’s important to note that zinc deficiency symptoms can vary between plant species, so it’s crucial to monitor the specific crops in question and adjust management practices accordingly. Regular soil testing and careful nutrient management are key components of preventing and addressing zinc deficiency in horticulture.