Fertiliser applications will need careful planning after a second consecutive wet winter and varying crop requirements, says agronomy firm Hutchinsons.
Indications are that heavy winter rainfall across much of
the UK could have increased losses of some of the more soluble
soil nutrients, such as nitrogen and sulphur, particularly on lighter, less nutrient retentive soils,
so it is important crop requirements are fulfilled as growth increases.
“We’re still waiting for results from N-Min testing, but my feeling is that given the rain we’ve had, there will be a low reservoir of nitrogen in the soil, and with crops generally showing good potential, it will be vital to protect that from the outset,” says agronomist David Stead.
“September-sown wheat looks healthy and well tillered, while even late October and early November-drilled cereals are nicely established with two to three tillers. We need to make sure we can maintain this biomass growth and not compromise the yield potential that’s there.”
Nitrogen is the main focus for early fertiliser as crop requirements increase significantly as canopies develop. Although N-Min tests are best done early in the year, Mr Stead says soil testing to gauge the extent of any winter losses can still help inform later applications.
Several other nutrients, notably phosphate, potassium and sulphur, influence how efficiently plants assimilate nitrogen. Magnesium is also important as it is fundamental to chlorophyll production and any shortfall reduces photosynthesis, which in turn reduces nitrogen uptake.