For products within the Cleancrop™ Brassica System range (Cleancrop™ Hawkestone swede, Cleancrop™ Firefly kale, Cleancrop™ bulb turnip, Cleancrop™ Toto turnip, Cleancrop™ leafy turnip and Cleancrop™ rape), follow the latest Cleancrop™ Brassica System Guide for best practice management and the stewardship plan.
Swedes should only be used in a first crop situation to prevent dry rot infection. A second crop alternative is kale.
If clubroot is likely to occur, Hawkestone or Clutha Gold are the better alternatives to other swede cultivars. Under high pressure from clubroot, kale should be used.
If there is a high risk of either dry rot or clubroot infection in the second year, it is recommended to sow the paddock in either a pasture or cereal crop.
In environments where brassica crops can be exposed to very cold conditions post-sowing followed by increasing temperatures, swedes should be sown no earlier than 20 November.
Earlier sowing combined with weather conditions can cause ‘vernalisation’, which means the plant believes it has been through winter and subsequently produces a seed head.
High yielding brassica crops have a large nutrient requirement. The nitrogen (N) requirements can range from 250 to 500kg N/ha. While total crop requirement for phosphorous (P) is quite low, it is vital during establishment and for shallow rooting brassicas. The application of P in a base dressing and down the spout at planting will provide good response particularly on low P soils. Growing brassicas on effluent ground may allow significant reduction in fertiliser inputs but again this should be on the basis of soil testing and knowledge of crop requirements.
The soil pH level should be at least 5.6 and ideally between 5.8 and 6.2 for most brassicas. Crops should have at least 40-60 kg phosphate/ha available at sowing.
Paddocks should have low soil sulphate levels. After grazing, a light application of nitrogen will greatly increase yields of subsequent growth. Use of nitrogen may increase problems of high crop nitrate content; test levels before grazing.