The effect of nitrogen and the method of application on yield and quality of white cabbage

During two seasons at three locations, six experiments were carried out to determine the effect of the amount of nitrogen and the method of application, broadcast vs. band placed, on the yield and quality of white cabbage (Brassica oleracea var. capitata). It was found that the crop could utilize the mineral nitrogen (Nmin) in the soil layer 0¿90 cm at planting, but no relation could be established between this mineral nitrogen and the optimum nitrogen application. The optimum nitrogen application is described as 330 kg N ha¿1 minus 1.5×the Nmin quantity (kg N ha¿1) present in the 0¿60 cm layer (=330¿1.5Nmin 0¿60 cm kg Nha¿1), applied broadcast at planting. Band placement of nitrogen fertilizer had varying effects on yield and is not recommended as a method to increase yield or to decrease the amount of fertilizer applied. Split application of nitrogen, as investigated in three experiments, showed no effects. Uniformity of individual head weight was positively or not influenced by increasing the nitrogen application. In one experiment band placement increased head uniformity. Shape of the heads was not or not consistently influenced. Relative core length increased with an increase in the amount of nitrogen applied.