We’re approaching the time of year when uptake of potassium (K) by the cotton plant can be restricted, reducing yield. The potassium requirement of cotton rapidly increases from early boll set, with 50% of total uptake occurring in the five weeks after first flower.

During peak requirements cotton can take up to 4-5 kg/ha of K per day. Developing bolls place a large demand on plant K reserves and plant uptake from soil, which can be compromised as root activity declines from early flowering. Shortages of K during this period can result in the fruit shedding, premature senescence, and yield loss.

Foliar potassium can play a key role  in supplementing crop requirements. Foliar applications of Easy Liquids K-FLOW range are an effective management tool for maintaining adequate plant concentrations or supplementing plant requirements when potassium uptake has been restricted by:

  • poor root growth
  • waterlogging
  • sodic soils
  • prolonged cloudy weather and low soil potassium levels

Easy Liquids K-FLOW 30, K-FLOW 12 and COMPLETE K can be used to pro-actively supply potassium in the case of potential shortages or to enable quick and effective correction of short-term deficiencies, preventing yield loss.

Table 1: Product analysis


Application recommendations

Soil surface applications of K are not effective on vertosol soils, so an in-crop foliar application option is a practical solution. Research has shown the optimum timing of foliar applications of potassium is between 2 and 3 weeks after the start of flowering (Figure 1).

Suggested rates and timing are:

  • K-FLOW 12: 2-3 applications of 30 L/ha 7 to 10 days from first flower
  • K-FLOW 30: 1-2 applications of 10 L/ha from first flower
  • COMPLETE K: 1-2 applications of 15 to 20 L/ha from first flower
Figure 1. Lint yield vs application weeks


The addition of an acidified wetter is critical. Target a final spray solution pH of 4 to maximise benefits of foliar applications.

Further information

For further information on EASY Liquids potassium options for Cotton please contact:

Matt Urquhart

Northern NSW / SE QLD

0429 789 298


Bob Moorfield

Southern NSW

0488 067 736