When should humic acid be used as a foliar spray on plants?

Humic acid is a natural organic substance derived from decomposed plant and animal matter. It is widely used in agriculture as a soil amendment to improve soil fertility and plant growth. However, it can also be used as a foliar spray on plants to provide additional benefits.

Benefits of using humic acid as a foliar spray

1. Enhanced nutrient uptake: Humic acid acts as a chelating agent, which means it binds to essential nutrients in the soil and makes them more available for plant uptake. When applied as a foliar spray, it can directly enhance the absorption of nutrients through the leaves, bypassing any soil deficiencies.

2. Improved plant health: Humic acid contains natural plant growth stimulants, such as auxins and cytokinins, which promote root development, flowering, and fruiting. When used as a foliar spray, it can stimulate plant growth and overall health, leading to increased yields and better crop quality.

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3. Increased stress tolerance: Plants treated with humic acid as a foliar spray have been found to exhibit improved tolerance to various environmental stresses, such as drought, heat, and disease. It helps plants to better cope with adverse conditions and maintain their productivity.

When to apply humic acid as a foliar spray

1. Early growth stages: It is recommended to start applying humic acid as a foliar spray during the early growth stages of plants. This is when the plants are actively developing their root systems and can benefit from the enhanced nutrient uptake and growth stimulation provided by humic acid.

2. Periods of nutrient deficiency: If plants show signs of nutrient deficiency, such as yellowing leaves or stunted growth, applying humic acid as a foliar spray can help address these issues. The chelating properties of humic acid can improve nutrient availability and quickly alleviate deficiencies.

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3. Stressful conditions: During periods of environmental stress, such as drought or extreme temperatures, plants may struggle to absorb nutrients efficiently from the soil. Applying humic acid as a foliar spray can provide a direct source of nutrients and growth stimulants, helping plants to better withstand and recover from stress.

Application guidelines

When using humic acid as a foliar spray, it is important to follow these guidelines:

1. Dilution: Dilute the humic acid concentrate according to the manufacturer’s instructions. Typically, a concentration of 1-2% is recommended for foliar application.

2. Timing: Apply the foliar spray during the cooler parts of the day, such as early morning or late afternoon, to minimize evaporation and maximize absorption.

3. Coverage: Ensure thorough coverage of the plant foliage, including both the upper and lower leaf surfaces. Use a fine mist sprayer or a sprayer with adjustable nozzles to achieve uniform coverage.

4. Frequency: Apply humic acid as a foliar spray at regular intervals throughout the growing season. The frequency may vary depending on the specific crop and its growth stage, so it is advisable to consult with agricultural experts or follow the product label instructions.

See also Humic acid and soil health

By following these guidelines, farmers and gardeners can effectively utilize humic acid as a foliar spray to enhance plant growth, improve nutrient uptake, and increase overall crop productivity.

Keywords: foliar, growth, plants, nutrient, uptake, nutrients, improve, better, stress