Soils with “Adequate” Potassium Levels May Still Need Application
Midwest recommendations often suggest growers need not apply potassium if soil test levels are above 170 ppm, but recent research has shown that application could pay off in a big way. Results from Dr. Robert Miller’s KRx project revealed that significant yield responses can be achieved from application in soils generally considered to have “adequate” soil test potassium levels – meaning potassium may be much more limiting than many growers think.
Yield Increases As A Result Of Applied K.
The research revealed yield responses to applied K fertilizers on soils as high as 290 parts per million, which far exceed what the land grant university critical values are.
