Crop advice archive

As January passes and the snow clears, attention needs to turn to the planning of nitrogen applications on arable crops. Firstly crops will need assessing to determine those to prioritise.

Canopy assessments can be anything from visual observations, shoot counts/m2, fresh weights etc to the use of remote sensing e.g. N Sensor.

Early nitrogen applications should be targeted at the small canopies of oilseeds and cereals to recover the biomass development that was lost during the dry autumn of 2009.

The same priority should also be given to second wheat’s to encourage early root and shoot growth which could be compromised by ‘take-all’.

HGCA R & D some years ago demonstrated the importance of early (late February), high rates (60-80 kgN/ha) of nitrogen to these second cereal crops.

I would also urge consideration into other possible limits to early growth, one of which could be phosphate availability. Cold, wet, heavy soils are examples where this can be an issue. On these soils an application of an N, P, K fertilizer, rather than straight nitrogen, would be particularly appropriate, helping to overcome some transient deficiency.

In addition to fresh fertilizer being used, foliar applications of phosphate (e.g. Magphos K) can be applied at the T0 timing.