This is provided the plants are evenly distributed and not excessively grazed by pigeons.
The optimum sowing interval for WOSR crops extends from mid-August (north) to early- September (south), although later sow dates can still deliver good crops.
These sowing dates can clash with harvest activities, making rapid and labour-saving establishment systems attractive.
While for best establishment the small rape seed ideally needs a fine, firm seedbed with good moisture conservation and a shallow sowing depth, good crops can still develop from lower establishment rates achieved with less precise sowing systems.
Sowing to a depth of 1.5cm is recommended.
Good establishment is critical for high yields and helps the crop withstand slug and pigeon attack as well as weed competition.
Ideally, cultivation should be done when soil conditions are dry, as rape does not like compaction.
However, the seedbed should be rolled as the rape seed is small and needs good seed-to-soil contact for rapid germination and successful establishment.
Trials from Teagasc Oak Park show that seeding rates should be 60-80 seeds/m2. These figures can be lowered when growing hybrid WOSR varieties.
Teagasc tillage specialist, Shay Phelan, addresses these issues on the latest Tillage Edge podcast.
“Oilseed rape does not like compacted soils. And, unfortunately, this is an issue in many parts of the country right now,” he explained.
“Compaction prevents root penetration. It also prevents plants from properly anchoring on the ground. Lodging will often follow, as will the poor uptake of nutrients.
“Particularly for growers looking at direct or min-till establishment options, they need to look at ways of relieving these compaction issues before they start drilling.”