Soils that are rich in potash are able to retain their water supply for longer periods, research suggests.


A study from the University of Gottingen, Germany, has suggested that soils well supplied with potash are able to hold 60 additional litres of water per cubic metre of soil.

Jerry McHoul, technical manager for K+S UK & Eire, estimated that this equates to a safety net of two weeks water supply to an actively growing crop.

“German growers have long recognised this and use K rotationally – applying their potash prior to the crop that needs it most – their oilseed rape,” he said.

“This, alongside poor magnesium use, is maybe one of the reasons why UK oilseed rape yields still lag some 0.5t/ha behind those in Germany.”

The study shows that potash could play an important role in creating a more consistent supply of water for crops, especially during drought seasons, he added.