Benefits of Foliar Nutrition

Foliar nutrition is a scientifically recognized method of delivering nutrient elements directly to where they are predominantly needed – foliage and fruit. It is particularly useful when nutrient absorption by the soil root system is negatively affected like during unfavourable climatic conditions and poor soil conditions (excessively high or low soil pH, etc). Foliar nutrition is also the method of choice for rapidly delivering nutrients during growth stages of peak demand. Foliar nutrition does not replace but supplement a sound soil fertilization programme. One of the most impressive benefits of foliar nutrition is its promotional effect on root nutrient absorption. This is probably due to the stimulation of the photosynthetic rate by foliar fertilizers containing N, K or Fe, Zn, Mn and Mg. More assimilates will promote root growth or its absorption efficacy in relation to nutrient ions. It follows that foliar nutrition can reduce soil pollution by reducing soil fertilizer input.

Foliar nutrition has become an established technique worldwide in all sectors of agriculture and horticulture. Foliar nutrition is used in both conventional and biological plant production systems. A lot of research activity is addressed on the further elucidation of the absorption mechanisms.

Foliar Absorption and Transport Mechanisms

Before being assimilated, a nutrient must obviously be absorbed by the leaf or fruit tissue. Fundamental steps of foliar nutrient absorption are as follows:

• Penetration through the cuticle. The cuticle is the first and most limiting barrier to foliar nutrient uptake.
• Penetration through the epidermal cell wall.
• Nutrient uptake into the cells.
• Distribution inside the plant as a function of nutrient mobility.

As an efficient absorption depends on good wetting of the leaf surface, on the pH of the spray solution and on many other parameters, the quality and the nutrient ratio of the formulation will determine absorption efficacy and agronomic performance. WUXAL Foliar fertilizers are equipped with special additives favoring excellent wetting, rainfastness and penetration of the nutrients involved. WUXAL products are formulated in such a way that they remain well compatible with most pesticides active ingredients.

Foliar Nutrition – When Necessary?

Foliar nutrition is particularly necessary during the following conditions:

• Visible and latent nutrient deficiencies.
• During critical stages with high nutrient demand and insufficient root absorption.
• Insufficient nutrient distribution within the plant (e.g. Ca, B in fruits).
• During physiological stress conditions (extreme weather conditions, frost damage, pesticide sprays, etc.).
• In order to maintain healthy and fully active foliage.

Foliar Nutrition and Plant Health

Properly nourished crops with nutrient elements like calcium, potassium or micronutrients will exhibit a higher natural resistance to insect pests and disease organisms than crops which are insufficiently supplied (e.g. fruits like apples, peaches, strawberries or table grapes are less sensitive to botrytis or monilia fruit rot if the fruit is enriched with calcium or specific micronutrients). According to our own results wheat plants well supplied with WUXAL Manganese were much less attacked by aphids than control plants suffering from manganese deficiency.

Formulated WUXAL Foliar fertilizers may also improve pesticide efficacy and thereby contribute to better plant health than from the pesticide alone.