History, cultivation and use
Rapeseed was already known to ancient Romans. It has been claimed that rapeseed was grown in South-Africa and in the Mediterranean area as early as 6,000 years ago.
Botanically speaking, rapeseed is a variety of turnip with bluish green leaves. Rapeseed has inherited this characteristic colour from a crossbreeding ancestor, the natural variety of cabbage. When a rapeseed field is in full bloom it looks like a thick yellow blanket. Rapeseed fields serve as abundant honey collection sources for bees.Rapeseed has spring and winter varieties. Spring rapeseed is sown in spring - it grows quickly and its green crop is ready for harvesting 55-65 days after sowing. Rapeseed is harvested when it starts to flower for the stems of the spring variety will become lignified soon. Rapeseed flourishes in territories of sufficiently high air moisture. Hence areas close to the sea are preferred. Its seeds are small, varying from greyish or brownish black to jet black.
Nowadays non-drying oil is manufactured of rapeseed which in the former times was used in oil lamps and for making Chinese ink.
Source: Heino Kiik “Maailma viljad” - Valgus, 1989