Switching to a controlled release fertiliser (CRF) has boosted the Jersey Royal Company’s yields by eight per cent, the potato grower has reported.
The Agromaster CRF fertiliser, which the firm substituted for a standard nitrogen fertiliser in trials last spring, also minimised leaching – the loss of plant nutrients from the soil, due to rain and irrigation.
Manufactered by ICL Speciality Fertilisers, the replacement fertiliser was applied to half of the six hectare field trial are at a rate of 180 kg of nitrogen per hectare. The other half of the test site was sprayed with a standard fertiliser, with both added two days before planting.
“When we monitored the crop, the earlier digs didn’t show much of a difference between the untreated control and the CRF-treated potatoes,” said technical manager Ryan Stone. “But after 12 weeks, the difference was clear and we saw up to eight per cent yield increase in some fields.”
He added: “From an environmental perspective, Agromaster helps to minimise leaching and this is extremely important for our farming practices. Reducing chemical residues is a very hot topic on our island.”
The findings demonstrate a significant opportunity for the Jersey Royal Company, which is responsible for 65 per cent (1,400 hectares) of Jersey’s total potato area. It exports 20,000 tonnes of the early-cropping variety to the UK mainland every year.
Potato growers are increasingly using CRFs, according to Scott Garnett from ICL Specialty Fertilizers. “They play an important role in improving yield, reducing nutrient losses and simplifying fertiliser application,” he said.
“It limits the need for top dressings and the fact that the fertiliser remains available to the plant over a longer period, offers vital nutritional support to the crop throughout the whole of the growing cycle.
“The way the technology works is simple, but highly effective. The fertiliser granules have an ‘E-max coating’, which is essentially a semi-permeable layer that controls the release of the fertiliser to the growing plant.
“This works in conjunction with the soil temperature and moisture content, with more fertiliser being made available as the soils warm-up,” Garnett added. “If the temperature then drops, the coating condenses and stops the flow of nutrients. When the nutrients are fully released, the E-max coating disintegrates harmlessly into the soil.”