15 August 2024
Harvest lull an opportunity to drill winter oilseed rape
With a lull in the harvest at the moment, Crops Specialist at Teagasc, Shay Phelan tells us why now is the opportune time to drill winter oilseed rape, while also offering key advice on variety selection and weed control.
As most spring barley is not yet fit and the ripe wheat crops are being harvested relatively quickly, there are actually jobs that can be done while waiting for crops to ripen, one such job is drilling winter oilseed rape crops.
Although it is usually sown after winter barley, it can often be difficult to find the time between harvesting straw, gathering straw and now stubble cultivation to actually get drilling done. That should not be the case this year.
Winter oilseed rape is a very useful break crop for all the various reasons like weed control, disease breaks, workload etc. But, at current prices, it also presents growers with the opportunity to leave a good margin.
Drilling dates
Drilling in most parts of the country will begin next week or after the 20th of August. Aim to sow early as it is unlikely there will be time when the main harvest kicks off in September. While you can drill up to mid-September, a day’s growth in August is worth a week’s growth in September, so earlier drilled crops are often better coming into the winter months which can help to reduce pigeon grazing. Earlier drilling can also reduce the impact of slugs and other pests, as the crop tends to grow that bit faster and get through the critical growth phases. Ensure that the crop is rolled immediately after drilling and this will help establishment and reduce the activity of slugs.
Variety selection
When choosing varieties, look at the traits such as pod shatter resistance, light leaf spot resistance, turnip mosaic virus resistance etc. as these traits play an important role in the final yield that can be achieved. Often we look at the overall yield rating of the variety first before looking at anything else. In winter oilseed rape, these traits play an important role in the overall yield being achieved.
Plant numbers and weed control
Aim to drill about 60-80 plants/m2 and establish 30-40 plants per m2. Once the crop emerges, keep an eye out for slug damage and if you suspect any then apply pellets.
The best weed control is usually achieved by using pre-emergence herbicides, as these tend to have a broader spectrum than post emergence herbicides, options include Butisan S/Rapsan 500 (1.5L/ha) or Katamaran Turbo (2.0L – 2.5L/ha) within 48 hours after sowing. Although there has been a trend over the last few years to wait until the weeds have emerged to apply a herbicide, the choice available is quite limited, with the exception of grass weeds or volunteers where there are plenty of choice of graminicides available.
Tillage Edge podcast
Shay Phelan and Ciaran Collins joined this week’s Tillage Edge podcast to share more insights on planning for winter oilseed rape. Listen in below: