The optimal date for sowing oilseed rape can vary widely. It all depends on the region, climatic conditions, as well as the specificity of a given place. Rapeseed sowing dates for most regions of Poland fall on August 15-25, only in the north-eastern part of Poland the sowing date falls on the beginning of the month (August 5-10). In practice, rape is sown from the first half of August to the beginning of September.
Proper sowing of rapeseed has a positive effect on the development of a strong root system and rape rosette. Sowing winter oilseed too early increases the risk of freezing-up due to the possibility of high plant growth. Late sowing of rape during unfavorable conditions of the autumn weather may lead to poor plant development. This may result in a lower chance of obtaining a high yield and less winter overwintering. With delayed sowing, the rate of sowing seeds per ha should be increased. The sowing date also influences the selection of the variety. In the case of winter oilseed rape varieties, the optimal sowing date begins on average 5 days earlier than in the case of hybrid varieties.
As for the autumn vegetation of winter oilseed rape, it is assumed that oilseed rape needs about 10-12 weeks of vegetation, so the sowing date should allow for the preservation of this period, as well as for the formation of a low-set rosette consisting of 8-10 leaves before winter, and a root collar with a diameter of at least one centimeter. It should be remembered that the yield of winter rape is formed already at the beginning of autumn vegetation in the 7-leaf stage, usually in the second half of October.
An important factor in sowing oilseed rape is the sowing depth of the seeds. Rapeseed is a fine-seeded plant, so its sowing must be quite shallow. Rapeseed sowing depth is assumed to be between 1.5 cm and 3.5 cm (depending on the type of soil). On heavy, compact and moist soils, shallower sowing is recommended. In turn, on light and desiccated soils, deeper sowing should be performed.
Sowing winter oilseed rape will be successful only if we follow the rules outlined above. Precise determination of the sowing date, selection of the right variety and depth, as well as the location in which winter oilseed rape will be grown - these are steps that should be successful when properly performed.
We also encourage you to read our articles on winter oilseed rape fertilization and rapeseed cultivation.