Zinc – Does It Pay?

More and more we hear about the importance of micronutrients – especially the importance of zinc. As a relatively new concept, many growers may wonder what that looks like and if it really pays to add zinc into their crop nutrition program.

Zinc is essential for growing and maintaining a healthy root system, aids in making other nutrients available, and is needed for early-season emergence and late-season seed production. In fact, the most common limiting factor on yield in a corn crop is being zinc deficient. For a 180-bushel corn crop, half a pound of zinc is needed. And although zinc exists in the soil, most of it exists in unavailable forms. Because of this, most crops can become zinc deficient pretty easily.

So, when will deficiency occur? Cool, wet soils in early planting conditions limit the availability of zinc, stunting root growth. This limits the ability for the plant to find new sources in the soil profile.

Now what forms do you use? In your starter, the most common form is a chelated zinc, like a chelated 9% applied in-furrow or a chelated 10% applied 2 by 2.

Why chelated? Chelation keeps a micronutrient from undesirable reactions. Chelated zinc is quickly taken up by the plant, which is why it is the preferred choice, but unfortunately is only available in liquid form.

The second-best and most commonly used form is zinc sulfate. This form is most recommended in no-till systems where fertilizer is banded near the seed. Another form is zinc oxide, which has low water solubility, so it is slower release, which provides higher season-long availability.

If you want to incorporate your zinc into your dry program, there are some great options that are easy products to get on the field. Microessentials SZ is an awesome source of Zn 1% – it has both zinc oxide and zinc sulfate. On top of that, it has an ammonium phosphate which is a more readily available form of phosphorous when compared to DAP.

YaraVita PROCOTE Zn is an exceptional zinc source. Being zinc oxide, it offers a longer availability. This PROCOTE is unique and is offered exclusively by Countryside-Landmark.  It’s a liquid form of zinc that coats the dry fertilizer you are spreading, ensuring growers can reliably and accurately spread an even distribution of zinc on a field.

If you have never used Zinc before and do not think it is needed because of the cost, let’s say October corn is $4.30/bu. At that price, you would need a 1.2-bushel yield increase with a chelated zinc, or 1.5-bushel yield increase with PROCOTE. Especially on your early season plantings, zinc can be easily applied and will help your plant with nutrient uptake all season long.

Reach out to your local agronomist to discuss which form of zinc is the best option for you to include in your spring fertilizer application.

Michaela Fox
Agronomy Account Manager