Foliar Fertilizer to Improve Plant Health and Increase Yield

FOLIAR FERTILIZATION

Foliar fertilization is any fertilizing substance applied in a liquid form.

"Foliar fertilization has been found to be the most efficient way to increase yield and improve plant health. Tests have shown that foliar feeding can increase yields from 12% to 25% when compared to conventional fertilization." (Source: Ecochem)

Tests, conducted in different locations, under different environmental conditions, have reflected the following;

1. When fertilizers are foliar applied, more than 90% of the fertilizer is utilized by the plant.  When a similar amount is applied to the soil, only 10 percent of it is utilized. 
2. In the sandy loam, foliar applied fertilizers are up to  20 times more effective when compared to soil applied fertilizers.

"Foliar feeding is an effective method for correcting soil deficiencies and overcoming the soil’s inability to transfer nutrients to the plant under low moisture conditions." (Source: Ecochem)

The effectiveness of foliar applied nutrients is determined by:

(1) The condition of the leaf surface, in particular the waxy cuticle. The cuticle is only partially permeable to water and dissolved nutrients, which can limit nutrient uptake.

(2) The length of time the nutrient remains dissolved in the solution on the leaf's surface.

(3) Diffusion, the movement of elements from a high concentration to a low concentration. For diffusion to occur, the nutrient must dissolve.

(4) The type of formulation. Water-soluble formulations generally work better for foliar applications as they are more easily absorbed when compared to insoluble solutions.

SOME RESULTS

University of Michigan - Drs. Witter and Turkey as quoted in Readers Digest magazine
"... leaves lap up food like blotting paper and it spreads in a few hours from tip to root.  In many cases, as much as 95 percent of the food sprayed on the leaves is used immediately by the plant, where under some conditions, the roots take up no more than 10 percent of the same amount placed in the soil."

University of Tennessee - Prof. T.S. Osborne, Agronomist
"... research indicated that only 10 to 12 per cent of phosphorus fertilizers as taken up by plants in the first year; the rest was "locked in" the soil or washed away. Fertilizer applied to soil is largely wasted because it is either bound by soil particles or is washed out of the root zone.  If chemical elements could go directly into leaves and bypass the wastefulness of soils, a tremendous saving would result.”

“... the foliage of plants can take in nutrients much as roots can.  Many nutrients are readily taken up by foliage, including bark of dormant trees; even at temperatures below freezing.  Elements such as phosphorus, nitrogen, and potassium move both up and down from the point of application at rates similar to those following root absorption."

GUIDELINES FOR FOLIAR FEEDING APPLICATIONS

• Use a sprayer that produces a fine mist.
• Nozzles should be turned to the back of the sprayers so the flow of material approaches the plant at a 90 degree angle to float on the plants.