Producers Blog

You’re reading Part 3 of a 4-part series. Start the series here.

Next is Phosphorus (P).

P is involved in energy transfer via adenosine triphosphate (ATP) and is a part of ribonucleic acid (RNA) and deoxyribonucleic acid (DNA). In more simplistic terms, P plays a major role in storing and transferring of energy for new cell growth. It is found throughout the plant, concentrating in leaves where photosynthesis takes place, and at growing points where energy for new growth is needed.

P has been linked to good root establishment and overall plant structure. P is not as naturally abundant in the soil as other macronutrients and is relatively immobile because of its negative charge that binds to positively charged particles, such as calcium. Therefore, soil erosion is usually the only way P can move off the field of application.

Recommended soil test levels: Again soil test recommendations differ regionally but optimum soil test levels would be above 30ppm (testing method being a Mehlich P-3 or Bray P-1). Deficient soil test levels would be less than 18ppm.

Deficiency characteristics: Slow growing, stunted plants with an inferior root system. The lower leaves have a tendency to become a reddish-purple color. The reddish color indicates an energy buildup that doesn’t have the ability to relocate. Plant standability and grain fill can also be compromised.

Crop removal: There is approximately .33lbs of P removed per bushel of grain. So, crop removal (from grain) would be 66# of P205 on 200bu/ac of corn.

Check out the whole series:

Part 1: Understanding NPK and Their Effect on Your Field

Part 2: Understanding Potassium and Its Effect on Your Field

Part 4: Understanding Nitrogen and Its Effect on Your Field

Ward, Raymond C., Ph.D. “Ward Laboratories, Inc.: WardGuide.” Ward Laboratories, Inc.: WardGuide. Ward Laboratories, Inc., n.d. Web. 29 Nov. 2016.