Rue is a strongly aromatic evergreen bush with yellow flowers. Finely chopped leaves can be added to sandwiches and salads. Height 40-60cm.
Often cultivated as a culinary and medicinal herb, the bruised leaves have a pleasant orange-like fragrance. It is one of the most pleasant herbs to inhale. Rue releases its scent in a remarkable way. The essential oil is contained in a cavity immediately beneath the surface of the leaf, above which is a thin layer of cells pierced by a cavity in the middle. The cells swell up and bend inwards, pressing on the essential oil beneath, which is driven to the surface of the leaf and there released.
Rue has a long history of use as a domestic remedy, being especially valued for its strengthening action on the eyes.
The growing or the dried plant can be used to repel insects, it is most useful when the plant is grown near roses and raspberries. The dried herb can also be put in the linen cupboard to repel moths. The growing plant is also said to repel cats.
A red dye is obtained from the plant. An essential oil is obtained from the leaves and young shoots, it is used in perfumery and as a food flavouring.
The plant was formerly used as a strewing herb.
Plants can be grown for ground cover when planted about 45cm apart each way. They can be trimmed back in spring to keep them bushy.
Succeeds in any soil but is hardier in a poor dry soil. Prefers an open sunny position. Prefers a partially shaded sheltered dry position but succeeds in full sun. Prefers a well-drained or rocky soil. Likes some lime in the soil.
Established plants are drought tolerant. Hardy to about -10°c, possibly to lower temperatures when it is grown in a dry soil.
Can be sown Autumn (preferable) or in early to mid spring in a cold frame. When they are large enough to handle, prick the seedlings out into individual pots and grow them on in the greenhouse for their first winter. Plant them out into their permanent positions in late spring or early summer, after the last expected frosts.
Leaves - raw or used as a seasoning. It is occasionally eaten in salads, but is strongly aromatic and slightly toxic, so should only be used in small quantities. The taste is strong and bitter. The leaves contain rutin, which has a beneficial effect upon the circulatory system. Some caution is advised: all parts of this plant are poisonous in large quantities. It should not be used at all by pregnant women since it can induce abortions. The sap contains furanocoumarins, sensitizing the skin to light and causing blistering or dermatitis in sensitive people. The leaves can be brewed into a tea.