Economical Use Efficiency of Phosphorus and Potassium
Application of phosphorus and potassium can be done simply, efficiently, and on time as you broadcast fertilizer across the field. However, how efficient is this application method for the plant to best utilize P & K? And most importantly, how economical is this method for your bottom line? Let’s find out.
The first step we need to analyze is P & K’s mobility within the soil and what method the plant uses to take the nutrients up.
Unlike nitrogen that is very mobile in the soil and can easily move to the root system by mass flow, or move within the soil via water, P & K is not very mobile and is tied to the soil particle.
Because of this, the plant must utilize the mechanism of diffusion (movement from a high concentration to low concentration) and root interception to take up P & K. Both processes must take place very close to the root of the plant in the soil.
As you can see in the chart below, only 93.7% of phosphorus and 80% potassium can be taken up by the plant in the root zone.
The second step is to determine how much of the soil profile is taken up by a plant’s root system.
You would assume on 30″ corn row spacing that a mature plant root structure would take up a large percentage of the soil profile and thus be able to effectively utilize much of the P & K that you applied.
In reality, it is only about 40% of the effective area of recovery within the soil profile. In other words, if P & K is only taken up by root interception or diffusion, then just 40% of the applied P & K by broadcast is available to the plant. Therefore, out of every $100 you spent on P & K, you are only efficiently utilizing $40 of the $100 spent. The rest of the $60 is left in the field and not utilized.
Here’s a good diagram to help you visualize this:
The key is to ask yourself how can you utilize the applied P & K more efficiently – and – more importantly, how can you be more efficient with the money spent on P & K to become more profitable.
If you’re successful, this change may also free up funds to utilize on other input products to make a healthier crop and maximize the yield potential of today’s genetics to their fullest potential. You are farming not only to create bushels but also to create profit. Therefore, together we should be analyzing the efficient use of your funds and calculating bushels created per dollar spent on the crop.
Options to utilize P & K more efficiently may include a combination of different practice changes of how to apply your fertilizer and what type of products you may be applying!
Reach out to your Liberty Ag Solutions Crop Input Consultant to discuss your operation and for help in guiding you through various options to more efficiently place your P & K on your field. We can offer expert advice on other nutrients to help you come out on top this year – and succeed!
