Nitro-Mag and KCL for Mid-Season Applications

All living things require Potassium in one form or another.  It is the third in line of nutrients listed as to their importance in plant growth.  NPK is always the first consideration when growers take stock of their soil and tissue test information.  Potassium or Potash is considered a Macro nutrient with Sulfur and Magnesium being Secondary nutrients.  Zinc and Boron and Manganese among others are the Micronutrients. 

Potassium Chloride or KCL is normally applied as a dry 0-0-60 granular product.  It as well as various forms of Phosphate are applied either in the fall of the year or early spring before planting.  

Potash was derived from the process of soaking wood ashes in water and then evaporating the water in large iron pots leaving behind a rich potassium salt residue.  It is literally the ash left in the pot which eventually was called potash.  In 1807 an English chemist named Sir Humphry Davy first isolated the pure metal element.  He named it Potassium as it was extracted directly from potash. 

The symbol for Potassium on the Periodic Table of Elements is K which is from the elements alternate name Kalium.   Its Atomic number is 19.  KCL as we know it is mined from ancient underground deposits.  Most of our supply comes from Saskatchewan Canada and New Mexico.  

Potassium’s role in plant health and growth is well documented.  K is essential to Chlorophyll production and in photosynthesis.  K also plays a key role in the transformation and translocation of sugars, starches, cellulose and other carbohydrates.  K along with Chloride controls the plant’s water usage and efficiency and in the regulation of the plant’s response to sunlight through the Stomata openings in the leaves.  

Those last listed roles that K provides are essential for plants as their usage rates go up as the season moves them into their reproductive phases.  Corn especially has a K usage rate higher than all the other nutrients, even nitrogen from V12 to the R3 stages.   Corn usage can be from 5 to 7 or more pounds per acre per day during this period.  This is the highest daily nutrient removal rate of any essential element in the corn plant.  

Knowing this, mid-season K deficiency is common even in high K soils.  Potassium moves mainly by diffusion, but a small percentage can be acquired by mass flow.  Diffusion is when nutrients such as K are in a high concentration in the soil and move towards the low concentration around the roots so that an equilibrium is reached.  Mass flow is when the nutrients such as Nitrate, Sulfate, Calcium or Magnesium are dissolved in the soil moisture and taken up by the plant as it takes up water for transpiration.  

Many soils may have a difficult time meeting this high K demand during the mid-season.   Straight Nitrogen applications during this time can increase K demand even more.  As the tissue test levels drop, a solution to this situation is to add K to the fertigation schedule.  Appling K with Nitrogen and sulfur if needed mid-season is a well proven technique that places the K directly in the active root zone during the peak demand.  Being added to the Nitro Mag Complex will help the K bypass the tie-up from the soil, especially in high-Mg or high clay soils. 

Nitro Mag K or Nitro Mag KS improves the K mobility and reduces the salt stress that you will find in a traditional 20-0-4 made with 32% and KCL.  The K is immediately available to the crop as is the Magnesium.  Pivot applications during this period ensure matching the daily K requirement.  Nitrogen builds the plant.  Potassium fills the ear. 

From R1 (Silking)stage to R4 (Dough) in corn, Potassium is the nutrient controlling sugar movement into the ear, kernel set and retention, kernel depth and test weight along with maintaining plant moisture retention.  

As you know I am an advocate for the nutrient Chloride.  It is called a micronutrient, but I am of the belief that it is very close to being a Secondary nutrient along with Magnesium. Many of the benefits of K are mirrored in what Cl will provide.  Chloride is required for Stomatal regulation, water movement and cooling, photosynthesis, and disease suppression.  

KCL often surpasses K2SO4 (Potassium Sulfate) in corn trails not because of the K but because of the Cl.  In the Nitro Mag Complex the Cl due to the complexing of the Mg and Urea are left as nutrients and not salts.   Potassium and Chloride work together as the Cl will enhance the Potash functions.  

Chloride is an important part of Nitro Mag.  Through the chemistry of the urea – MgCl complex that features Ion Shielded Technology the high salt content of MgCl is shielded by the Urea and the Mg. This makes Chloride more user friendly than if you were to apply MgCl directly to the soil.  

Corn will remove 10 – 20 pounds of Cl per season.  Much of the soil in our area is very low in Chloride and will benefit from having it in the Nitro Mag K or KS application.  As stated, Chloride is not a trace element it can be a macro-anion used daily by the plants. 

GT products Nitro Mag K and KS have lower salt than traditional fertilizers available for the mid-season fertigation applications for corn and soybeans and other crops. Years of testing have proven their ability to provide K at a critical in the plant’s growth anddevelopment.                                                                                                     

Read more about Nitro-Mag in "The Basics of Nitro-Mag" HERE

Marcus Dennis