Crop nutrition research from the fields

My soil test shows I am low in both P and K and I only have money to fertilize with one. Which do you suggest would be most beneficial to my crops (corn / beans)?

Robert Mullen, Ph.D.

Robert Mullen

Robert Mullen, Ph.D.


Director of Agronomy

To say Dr. Robert Mullen is passionate about agriculture would be an understatement. He holds a Bachelor of Science degree in ag business from Cameron University, along with a Master of Science degree in plant and soil science and a Ph.D. in soil science from Oklahoma State University. In addition, Dr. Mullen has been published in a variety of scientific and trade journals. But it’s not just his academic accomplishments that make him unique. It’s his unwavering ability to take complex data and — in simple terms — explain how it impacts a farmer’s bottom line. Dr. Mullen delivers the kind of insightful observations that can lead to a more profitable business. As a leading agronomy expert, Dr. Mullen has a goal to further educate farmers on best management practices that improve their yields and maximize their return on investment.

Share This:

While, ideally, you should apply both nutrients if they are limiting production based upon soil test, there is some research to suggest that just applying K can be more beneficial than just applying P if both are limiting. Also, check out our Nutrient ROI Calculator to show you the dividends you can reap with an investment in both P & K.