Foliar fertilization for nutrient use efficiency

Abstract

Foliar fertilization is a practice where plants absorb nutrients directly through their leaves via spraying, complementing conventional soil-based fertilization. This method improves nutrient absorption, especially for secondary nutrients and micronutrients like calcium, magnesium, zinc, and iron, which might not be sufficiently available in soil. It can be particularly beneficial during critical growth phases or when root absorption is limited, such as during periods of water stress. While foliar feeding should not replace soil fertilization, it serves as a supplement, enhancing the plant's growth and productivity. For effective foliar application, proper timing, plant condition, and meteorological factors such as temperature, humidity, and wind are crucial. Foliar feeding provides a rapid delivery of nutrients, especially in times of nutrient deficiency or environmental stress, boosting plant resilience. Essential for success, the fertilizers used must be water-soluble, with a low molecular weight and appropriate pH, ensuring minimal risk of phytotoxicity. The approach is gaining popularity in horticultural crops, although its use in larger agronomic crops remains less widespread. The strategic use of foliar sprays can extend growth, delay senescence, and support recovery from adverse conditions, ultimately enhancing crop yield.