Growing winter crops is an integral part of most farm programmes – important for supplying winter feed and as a break crop for a regrassing programme.
Kale is one of the best forage crops to plant and Ravensdown recommend that early planning is essential to get the best returns.
Huw Murray, Ravensdown’s Technical Manager Agronomy, says weed issues and nutrient deficiencies need to be addressed prior to establishing any winter crop, and selecting paddocks for regrassing should be based on paddock Dry Matter (DM) performance.
“This is usually the oldest paddocks, where native grass species are taking over and clover is thinning out. Judicious selection of the poorest paddocks on the farm will have the biggest gains in production, provided the performance issues are addressed,” he says.
Soil testing should take place at least the autumn before, and the necessary capital lime or fertiliser applied to ensure the fertility of the paddock.
“Lime takes time to exert the effect, so if pH levels are low, the lime needs to be applied 6-9 months before the crop goes in. And it is always wise to check for weeds before doing so. If they are prevalent a pre-emergence spray will be necessary,” says Huw.
Among the major decisions to be made is the selection of an appropriate cultivar for either sheep (short variety) or cattle (medium leafy variety).
Cultivation then drilling or direct drilling are the two common methods of paddock preparation, and each has its advantages and disadvantages. For direct drilled crops slug bait is essential, he says.
“Both forms will benefit from sowing with fertiliser i.e. DAP to ensure nutrients are near the seed.
“Kale is best sown when soil temperatures are at 10-12 degrees celcius and rising (usually around November). If the crop is not able to be planted early enough, another option is winter rape.”
Kale is usually sown at 4-5kg per hectare, but Huw Murray says a greater yield can result if it is sown at 5kg per hectare, with the promotion of finer stems and more leaf. Treated seed will protect the germinating kale from insects.
Once the crop is up and actively growing the main job is to monitor and address weeds and insects. Ravensdown also recommends that herbage testing throughout this time can be very beneficial.
One or two side dressings of urea can be applied depending on the crop yield potential as well as the soil nitrogen reserves.