Polysulphate shows up well in Maris Piper trials for ICL

In North Yorkshire, a crop of the variety Brooke was grown on a sandy loam soil. The split field trial sought to assess the potential for Polysulphate or PotashpluS to replace GMOP. Three rates of Polysulphate were applied – 100, 200 and 300kg/ha – and PotashpluS was applied at 895kg/ha. These treatments were compared with a control of granular muriate of potash applied at 550kg/ha.

These treatments applied nutrients as above

Polysulphate was applied just before planting, while potash products were applied a month earlier. “The trials bear out findings from previous years of the benefits of our products for the crop,” pointed out ICL agronomist, Scott Garnett.

The trial sites were harvested using five 2m replicated digs from each treatment. Total yield was recorded along with four graded outputs. While all treatments increased total and marketable yield compared to control, the best result was achieved from Polysulphate applied at 100kg/ha.

A second trial in North Lincolnshire using Maris Piper, again grown on a sandy loam with a soil analysis of potassium – index 2; magnesium – index 5; phosphate – index 2 and pH 7.1. This split field trial explored the effect of sulphur on potato production using Polysulphate as the sole source of S.

In this trial Polyphosphate boosted marketable yield by 18% compared to the control

An application of 200kg/ha of Polysulphate was added to the standard farm practice and in this trial, Polyphosphate boosted marketable yield by 18%, compared to control.

Polysulphate fertiliser comes from a polyhalite layer of rock, mined over 1000m below the North Sea off the North Yorkshire coast in the UK. It is available as granular and powder products and contains four key plant nutrients – sulphur, potassium, magnesium and calcium.