Twelve Critical Days of Summer

Since your corn crop is off to a great start, it is time to evaluate if all your nutrient needs have been set up to achieve high yields. Foundational fertility is always the essential link to building higher yields. If you’ve tested your soils and applied the necessary nutrients, what’s next?


The secret to achieving high yields, is to set up your whole fertility system to support maximum nutrient uptake, which occurs in the 12 days leading up to pollen shed. During these stages of growth, the plant continues to grow while beginning to transition into ear development and grain fill. In these 12 critical days, the nutrient demand from the plant is huge. Your corn crop will demand 40+% of the total Nitrogen, 40-50% of the total Potassium, and 20+% of the total Phosphorus it will use during the growing season. Here is what that looks like. 250-bushel corn will need 100+ lbs of Nitrogen, 120-130 lbs of Potassium, and 20-25 lbs of Phosphorus during those 12 peak uptake days. This is why foundational fertility is so critical.


Your soil needs a deep reservoir of nutrients in proper balance of both macro and micro nutrients for the plant to be able to achieve maximum nutrient uptake. The corn plants must have a large and strong root system established, and the soil needs to have enough moisture to mobilize the nutrients and recharge the root zone as the plant draws from the available resources.


Growers today manage their nutrient supply by timing the applications of nutrients to match the peak uptake needs of the plant. Side-dress applications of Nitrogen and Potassium help growers achieve that goal. The use of Nitrogen stabilizers like N-Ergize are also helpful in managing nutrient availability. University research results tell us that up to 30% of the applied Nitrogen is at risk to volatilization and/or denitrification. The cost of Nitrogen stabilizers is 1-2 bu/acre of corn, and the potential is there to save more of the Nitrogen that is applied.

A combine in the field.

You can monitor your nutrient use efficiency by doing tissue samples of the corn on a weekly basis, starting at V6 stage of growth through brown silk. Deficiencies can be addressed by applying more nutrients through the soil or utilizing highly efficient foliar macro and micronutrients. With commodity prices lower, it is important that you make fertility decisions that provide a positive return on your bottom line profitability.