In the winter of 2013, AgriEnergy Resources somehow managed to coax the University of Nebraska’s Dr. Roch Gaussoin to present a detailed analysis of his research on foliar feeding.
The 137-slide presentation, titled “Foliar Feeding DOES work” blows away most of the misconceptions about enhancing crop yields and health with foliar-applied nutrition. With Dr. Gaussoin’s permission, we obtained a copy of that PowerPoint show. This report contains the links to it, plus the “Cliff notes” highlights.
It would obviously carry more punch if you could hear Dr. Gaussoin’s explanations with each slide — but the pages are fairly descriptive. Dr. Gaussoin is a turf grass specialist, but the principles apply to all crops.
We split the presentation into “takes” of 30 slides or fewer, so you can download sections of it without choking your web browser. We converted the PowerPoint presentation into PDF (Portable Document File) format, so anyone with Adobe Acrobat Reader can open and read it.
This report offers the bullet points which are more fully explained in the presentation itself.
Key points from slides 1-30
1. Foliar uptake of nutrients has been documented thoroughly.
2. It’s a misconception that foliars enter through stomata. They enter through the cuticle via “nanopores.” These leaf pores are called “Ectodesmata” and are very small; less than one nanometer. Solutes such as urea move through readily. (A WakeUP colloid is about 0.8 nanometer)
3. Uncharged molecules move readily when in solution, but not if they’ve dried on the leaf surface. So it’s important for nutrient elements to penetrate quickly, within a few seconds.
4. Increased hydration (more water) improves penetration (permeation) because it weakens ionic charges of the nutrients.
5. Nutrients absorbed through leaves enter cell walls the same way as ions absorbed by roots. The myth that leaves can’t absorb nutrients has been disproven for decades.
6. Foliar-applied nitrogen is 30% to 99% absorbed. (Yet, one of our Iowa clients heard an extension agronomist tell him, “Leaves can’t absorb nitrogen. Only roots can.”) Soil-applied nitrogen is only 10% to 40% recovered. Up to 90% of soil-applied N is lost to groundwater leaching.
7. Surfactants are beneficial to critically important.
8. Spray solution pH should be slightly acidic to neutral. Leaf nanopores are negatively charged, so a chelator is beneficial to neutralize the positive charge of most micronutrient metals (manganese, zinc, etc.)
9. Foliar-applied nutrients are immediately available to plant metabolism.
10. Foliar applications allow for varying rates depending on the crop’s analyzed need for nutrients.
11. “Organic facilitators” bind substantial amounts of nutrient metals. These include humic acids, fulvic acids, glucoheptinates, amino acids, citric acid, and others (look closely at the important slide on this subject). WakeUP Summer performs the job of an “organic facilitator” because it’s formulated with plant based oils, alcohols, and oleic acids.
12. Using plant-based or organic sources as foliar nutrient complexing agents is beneficial because they are “less phytotoxic” and provide an energy source to microorganisms.
We suggest that you print out the PDF of each slide section… the whole show is a “keeper” worthy of a 3-ring binder in your farm office.
Key points from slides 31-60
1. Properly formulated, non-ionic surfactants and other related products are “better absorbed because they are non-ionic.” They assist in plant uptake and translocation. (Our commentary: This is exactly what WakeUP Summer is formulated to do.)
2. In a normal application of NPK foliars on grass, 70% of the nutrients are absorbed into plant metabolism after two hours. (Our commentary: WakeUP Summer accelerates this penetration. Leaves will appear dry within 10 to 20 minutes because the glossy spray coat has been absorbed.)
3. Calcium and Magnesium are absorbed more slowly, but most other metal micros are quickly taken up.
4. Spraying time of day makes little difference in absorption. Temperature is probably more important. Ambient temps around 70 degrees are favorable, and a little later in the day usually brings slightly warmer temps.
5. The nitrate form of nitrogen is more quickly absorbed through leaves and into plant cells than the Urea form. The carrier or surfactant will influence speed of absorption.
Key points from slides 61-90
1. Foliar feeding can amplify movement of photosynthetically built carbohydrates to the roots. About half of leaf carbohydrates are sent to roots, which excrete to the soil about half of the nutrients they receive. Soil organisms use this energy to break down mineral nutrients which plants take up.
2. Foliar nutrient absorption is physical and chemical and happens quickly.
3. Foliar feeding is especially helpful if root structure is poor, crops are stressed (such as dry weather), or you have pH problems in the soil which block uptake of certain micronutrients. (Our comment: See the slide showing how availability of micronutrients varies by soil pH)
4. Even with optimum soil fertility, there’s not always a continuous supply of nutrients to the plant.
5. Foliar fertilization is by far the most effective way to apply secondary and trace elements.
6. By making essential micronutrients available, foliar feeding can increase uptake of soil fertility, reducing total fertilizer needed.
7. Foliar nutrients increase chlorophyll production, which in turn increases uptake of soil-applied fertilizer.
8. Early, cold and wet conditions constrain soil organisms and hamper soil nutrient availability. Foliar feeding gives nutrients immediately, jump-starting growth until soil warms up.
Key points from the fourth group of 14 slides
1. Check the label on the foliar nutrient product to see if you need a buffering agent. If you are tank-mixing several products, a buffering agent may help.
2. Check pH with a reliable meter or pH paper.
Key points from the fifth group, which is 16 slides
1. Phosphite salts are sometimes being recommended to increase plant health and resist soil pathogens.
2. Phosphite is not considered a nutrient which substitutes for the typical forms of phosphorus fertilizers.
Key points from the final group of 18 slides
1. The University of Nebraska is experimenting with organic acids which could be foliar applied to amplify certain growth processes like root development.
2. Low dose, frequent foliar applications have definite agronomic benefits.