Compared to other vegetable crops, cauliflower and broccoli are extremely perishable and should be stored for relatively short periods. Leafy brassicas are less demanding in terms of harvest timing. Here, leaf nutrition is the key: ensuring good green, strong plants will help secure good quality and a long shelf life.
By getting brassica crop nutrition right, the grower brings forward harvest and consistently improves head, curd and leaf quality. This can have a significant, positive effect on marketable yield, produce grade, price and profitability.
If optimum nitrogen rates are exceeded it can have a negative impact on storage quality. It can result in low dry matter content – which reduces the storage quality of cabbage, and can lead to greater disease in the stored crop, particularly in susceptible varieties.
Adequate potassium supply ensures a more marketable crop and with a healthy longer shelf life and less moisture loss during storage.
Magnesium improves brassica crop storage characteristics. Magnesium uptake can be depressed by an excess of other cations (K+; NH4+; Ca2+), so it is important to maintain a correct balance to avoid compromising Mg uptake. Mg-salts (e.g. carbonate, nitrate and sulfate) are more soluble than Ca-salts but also more prone to leaching losses. Foliar sprays can be used to correct acute deficiencies.
Sulfur has a major role to play in brassica crop quality. Application of sulfur in the form of SOP (Potassium sulfate) increases dry matter content of white cabbage, which gives better storage quality.