Phosphorous And Potassium
Every nutrient in the soil has a job to do. For example, potassium stimulates early growth, improves the efficiency of water use, and resistance to diseases and insects. Phosphorous helps the plant store and transfer energy during growth and reproduction. If you don’t have enough of these nutrients, you’re leaving profit potential in the field.
Matt Clover is the agronomy manager for Dupont Pioneer. He says over the last couple of years, they did thousands of soil tests across the corn belt checking for phosphorous and potassium.
"The results came back quite astounding. As we look at the range across the corn belt, 12 states, almost 9,000 samples taken, we came back and we saw that anywhere from 20%-75% of those soils tested very low or low," says Clover. "So that means we’re trying to maintain these very high yields like we saw in 2016 and 2017 in soils that are kind of deficient in these nutrients."
Is your soil low on potassium and phosphorous? Clover says you won’t know unless you do a soil test.
"If you haven’t taken a soil test in the last, say, 1-2 years, go out and take one again. Know what the current fertility levels are of your soil. Second, try to have a good idea of what your yields are. Granted, it’s in the future, we can’t predict everything, but we know that as yields go up, so do those phosphorous and potassium levels," he says. "The removal that’s being taken off the field, it’s a direct linear trend, so if we can have a good assessment of what that yield level’s going to be, we can better apply what we need for that field."
While corn and soybean yields have risen substantially over the last 30-years, phosphorous and potassium fertilizer applications haven’t necessarily kept pace.
Learn more about the study results and how it might apply to your farm.