Winter oilseed rape can be nutrient hungry during the establishment stage and here, industry expert, Bill Petrie, zeroes in on the benefit of phosphorus.

‘Phosphorus is key and underpins all the elements. It only moves in the soil approximately 2mm/week and has a negative charge – this means that all positively charged nutrients can lock on to the ‘P’ and as a result ‘lock-up’ the benefits of phosphorus.

‘It has been recorded that up to 90% of the applied phosphorus becomes lock-up and is not available to increase the ‘root miles’. The root miles of plants in the first six weeks are key to potential of the crop.

‘Nutricharge-treated phosphate, available from Glasson Fertilisers, reduces lock-up, by increasing root miles and yield.

‘Applications of nitrogen can prove ineffective without adequate phosphorus and fewer root miles have been recorded. The off-take of P2o5 /tonne of seed is 14 kg – so five-tonne/ha = 70kg/ha with 11kg/t Ko2 = 55kg/ha. That’s a P to K ratio of 1.3 to 1. (see table for results).

‘OSR also has a requirement for both calcium and boron, plus an application of lime will improve the soil pH, but will also supply 50-54kg CaO/100kg of product.

‘Boron increases establishment and growth and remember that soils with a high iron level in the soil can effect phosphorus and boron uptake by plants.

‘Adequate P2o5 changes the growth habit of the plant by creating a bushy plant both above and be low ground.’