No matter how timely you are with scouting and spraying your cotton, if your N, P, and K aren’t right then you cant maximize the potential of the plant. We all know this but what we cant figure out is why we’ve been having Potassium problems here recently. We had a good bit of rain this year so that could be one theory however Potassium isn’t as mobile as Nitrogen and we seemed to do well with our Nitrogen levels. Dr. Glenn Harris has a theory that elevated Calcium levels are reducing Potassium uptake. People are pushing pH levels higher which usually results in higher Calcium levels. It’s a pretty sound theory. Until we get it figured out here are a few things we can do to help alleviate our Potassium problems.
- Soil Sample-Make sure you’re getting the right amount out there.
- Don’t split-Put it all out at planting, do not split the Potash applications.
- Foliar-Two rounds of K2O, (5-10lbs) during early bloom (1st-4th week of bloom).