Coleseed (Brassica napus arvensis)

Annual/Biennial
Common Name Latin Name Plant Family
Coleseed
Brassica napus arvensis
Cruciferae

The seed contains up to 45% of an edible semi-drying oil, it is used as a luminant, lubricant, in soap making etc[13, 21, 57, 142].

A good green manure, the deep taproot improves drainage and loosens heavy soils[18, 20, 87].

  • Medicinal Use

    The root is emollient and diuretic[240]. The juice of the roots is used in the treatment of chronic coughs and bronchial catarrh[240, 269].

    The seed, powdered, with salt is said to be a folk remedy for cancer[269].

    Rape oil is used in massage and oil baths, it is believed to strengthen the skin and keep it cool and healthy. With camphor it is applied as a remedy for rheumatism and stiff joints[269].

  • Edible Use

    Leaves – raw or cooked[4, 34, 37]. Added to salads or used as a potherb[183].

    Immature flowering stems – cooked in much the same way as broccoli[183].

    An edible oil is obtained from the seed, it is used mainly for cooking purposes, but also for salads[4, 13, 34, 46, 183]. Some caution is advised, see the notes above on toxicity.

    The sprouted seed is often used as the mustard part of mustard and cress. Eaten in salads[4, 34, 37, 183].

    The seed is used as a mustard flavouring[183].

  • Cautionary Notes

    The oil contained in the seed of some varieties of this species can be rich in erucic acid which is toxic. However, modern cultivars have been selected which are almost free of erucic acid.

Cultivation & Habitat

Seed – sow in situ in early spring to mid-August for a green manure crop.
Succeeds in full sun in a well-drained fertile preferably alkaline soil[200]. Succeeds in any reasonable soil[52]. Prefers a heavy soil and cool moist conditions[16, 20]. Sunny days and cool nights are favourable for plant growth whilst dry weather at harvest time is essential[269]. Coleseed is reported to tolerate an annual precipitation of 30 to 280cm, an annual average temperature range of 5 to 27¡C and a pH in the range of 4.2 to 8.2[269]. Very young plants are susceptible to cold damage, -4¡C either killing or injuring seedlings, whereas -2¡C has no affect when the plants are more than one month old[269]. Coleseed is the form of this species most often found either escaped or naturalized in Britain. It has a non-tuberous root and has been cultivated as a fodder crop, oil-seed crop and green manure[17]. Coleseed is 70% self-pollinating and 30% cross-pollinated. Even if wind and insects are absent, seed are still produced. Yield increases with honeybees[269]. The growth of this plant is inhibited by field mustard and hedge mustard growing nearby[18, 20]. This species is closely related to B. rapa[200].
Europe – Mediterranean. Naturalized in Britain[17].

Become ungovernable, break the chains of the matrix; grow and forage your own food and medicine.

*None of the information on this website qualifies as professional medical advice. Take only what resonates with your heart and use your own personal responsibility for what’s best for you. For more information [brackets] [000], see bibliography.