With increasing numbers of growers opting for spring-sown crops to help them tackle blackgrass but complex nutrient interactions determining the final value of the most popular spring barley option, accurate N management is essential, says Allison Grundy.
“Spring crops have a lot of growing to do in a short period of time so you have to use nutrients wisely and get them into the crop efficiently to get the best out of them.“It’s complicated by the fact that many people are aiming for malting markets to maximise value, but if you use N inputs without understanding exact crop needs you can end up with excessive Nitrogen in the grain and a rejected crop.
“The top priority is to know what Nitrogen the crops already have available to them from the soil and this is where N-Min followed by N-Calc is essential.”
At John Rowsell Ltd’s West Stoke Farm in Hampshire, the approach followed by Heartland Sulphur (24N 8P 8K 8SO3) added 1.0t/ha to spring barley yields and returned an extra £175/ha margin over fertiliser costs.
Crops using the approach delivered up to 8.34t/ha despite the dry spring and resulting poor germination, compared to an average of 7.3t/ha for the farm's standard fertiliser practice.