By Luke Schulte, CCA, Beck’s Field agronomist
For many reasons, fertilizer prices have been on the rise for some time. Due to significantly higher prices, some farmers may have chosen to apply less or perhaps skip dry fertilizer applications altogether. However, proper nutrition is fundamental to maximizing yield potential and is increasingly important to profitability in times of high commodity prices.
Foliar nutrition products are often labeled “snake oils”. Although some foliar products have not been consistent, it is important to recognize that it is not as simple as prescribing a product that contains the nutrients that the soil or crop lacks. Compared to dry fertilizer, the volume of nutrients in a foliar feeding program is minute. Therefore, it is imperative to focus on successfully getting the low volume of nutrients into the plant to capitalize on its effectiveness. Inclusion of the following components in a foliar program will lead to a greater likelihood of uptake by plants.
Components to maximize absorption.
- Fulvic acid: Fulvic acids are powerful chelators and are very small molecules. Size and the ability to form strong complexes with nutrients have a significant impact on nutrient intake.
Fulvic acids also serve as antioxidants. Simply put, they help plants combat stresses, such as excess moisture or drought, by minimizing the compromise of nearby cellular components. By minimizing cell destruction, the plant does not spend energy for cell repair, therefore more energy for growth and the accumulation of dry matter. The Versa Max product line from Rosen’s Incorporated each contains a fulvic acid.
- Potassium Acetate: Potassium is a large molecule and difficult to feed through the leaves. However, the potassium source can have a significant impact on plant uptake. Foliar feeds derived from potassium acetate are much more likely (>500%) to be taken up by plant tissues. Potassium plays a central role in soybean flower initiation and regulates water vapor exchange (keeps the plant hydrated). Potassium acetate is also an antioxidant.
- Water Conditioners: The most important component of any spray solution that touches the plant is the water component. Water sources vary widely from region to region, but much of the water from wells is considered “hard.” Hard water is caused by high levels of cations (mainly Ca, Mg and Na) and often has an alkaline pH. These hard water minerals can be antagonistic, inhibiting the effectiveness of the spray solution. BRANDT Indicates 5 works as a water conditioner that counteracts the effect of hard water and an acidifier. This conditioner has a built-in pH indicator that turns spray water pink when a pH level of 4.5-5.5 is reached. Choice Trio acts as a water conditioner by sequestering, chelating and complexing hard water cations.
- Adjuvant Technology: Adjuvants are designed to help get more of a pesticide, fungicide or foliar nutrient into the plant. How they do this varies, but those that are successful in increasing the speed of moisture absorption and retention generally work more consistently. Winfield United’s MAX-IN products (listed above) contain CornSorb Technology, which is a culture-based adjuvant designed to do just that – increase wetting and absorption.
- Time of day: As you read this, many acres of corn and soybeans are entering crucial yield-determining stages – flowering and ear initiation (about V5/V6). Plant health, vigor and nutrition all play a critical role in maximizing the volume and size of these plant components. Applying foliar nutrients in the morning or during cooler hours is more effective and cost effective than applications made in the heat of the day.
This happens for several reasons.
- Dew and respired water are more abundant on the leaf surface in the morning. This extra moisture can act as an extra medium to get more nutrition into the plant.
- Cooler temperatures allow plants to retain moisture longer, which slows evaporation rates.
- The stomata (the small pores or openings on the underside of the leaves) are opened in the morning, allowing for increased absorption.
Whether or not you choose to apply a dry fertilizer before this crop, nutrition is key to maximizing growth and efficiency and overcoming abiotic stress. Don’t just check the box; it’s better to make sure your foliar investment is making it into the plant and making a difference.