Rapeseed: The Golden Oil Fruit From the Field

In spring, rapeseed cannot be overlooked in northern Germany. In Lower Saxony alone, the yellow flowers light up well over 100,000 hectares or 1,000 square kilometers of farmland for around four weeks. This so-called winter rape is already sown in late summer and, as a young plant, even survives icy and snowy winters.

A valuable oil for kitchen and industry

Farmers primarily grow rapeseed as an oil crop, because the seeds contain around 45 percent oil. Many households use high-quality and versatile rapeseed oil in the kitchen. It is also found in margarine and is processed into biodegradable lubricants, hydraulic oil, and biodiesel. After the oil has been pressed from the small, dark rapeseeds, these are used as protein-rich animal feed for cattle, pigs, and poultry. The chopped straw is then used as absorbent bedding for stables.

First the honey, then the oil

But not only the mature plants are used. During the flowering period, beekeepers like to set up their colonies near the fields, because bees collect nectar for up to 100 kilograms of honey from one hectare. Rapeseed honey has a mild taste, a creamy consistency, and a white to light beige color.

A fairly young crop

Around 70 different rapeseed varieties are approved in Germany alone. In this way, farmers can select the right varieties based on the special conditions of their soil and the regional climate. Although oilseed rape is a plant that is thousands of years old, it has only recently played a role in human nutrition. Early varieties contained the incompatible substances erucic acid and glucosinolates. Rapeseed oil was initially used as lamp oil. It was not until the 1970s that breeders succeeded in removing these substances and cultivating the so-called double-zero rapeseed (00 rapeseed). This marked the beginning of the rise of oilseed rape as an edible oil and fodder crop. After soybeans, it is now the most commonly cultivated oil crop worldwide.

Brassica napus: A cruciferous plant

Oilseed rape, which biologists call Brassica napus, belongs to the cruciferous family. The annual plant has a taproot, is 30 to 150 centimeters high depending on the variety, and prefers nutrient-rich, deep soil. The yellow flowers are on a two to three-centimeter-long fruit stalk. When ripe, they become narrow pods, almost ten centimeters long, each containing up to 20 seeds.