Barberry

The common barberry (Berberis vulgaris) is a deciduous, thorny shrub from the barberry family (Berberidaceae) that grows to a height of 1 to 3 metres. It is characterised by its alternate, simple leaves, which are obovate to elliptical in shape and turn an intense yellow-orange to orange-red colour in autumn. The branches bear one to seven thorns, which serve as protection against animals. The bark is yellow-brown to grey on the outside and bright yellow on the inside.

Growth, location and soil requirements of barberry

The plant grows in western, central and southern Europe, but not in the British Isles or Scandinavia. Its distribution extends eastwards to the Caucasus, including Turkey, northern Iran and Uzbekistan. Its natural range extends north to Scotland, Norway (Trondheim), southern Sweden and the Baltic States, and south to southern Spain, central Italy, northern Greece and Asia Minor. In the Alps, barberry grows at altitudes of up to around 2,500 metres, and in some regions even up to 2,660 metres.

Barberry grows upright to spreading and bushy. It prefers sunny to semi-shaded locations in well-drained soils, which can be neutral to slightly acidic or alkaline. It is tolerant of lime and thrives in various soil types such as stony, sandy, loamy or clayey, with moderate soil moisture being ideal. The plant is robust, undemanding and very tolerant of pruning.

Barberries are valuable for biodiversity: they provide food for insects, nesting and shelter for birds, and hiding places for hedgehogs. The thorns protect them from predators. A remarkable behaviour of barberries is their ability to selectively kill seeds to protect themselves against parasites, which indicates complex plant decision-making.

Flower and fruit

The yellow, fragrant flowers appear in hanging clusters from May to June and attract numerous pollinators such as bees and butterflies. From September onwards, small, bright red, elliptical berries up to 1 cm long ripen. They are edible, very sour, rich in vitamin C and are often used in jams, jellies or as a seasoning. Birds like to eat the berries in winter, thus spreading the seeds. The entire plant except for the berries is poisonous. The scarlet berries, which are up to one centimetre long, are edible but very sour. However, they can be eaten dried as an alternative to raisins or made into jam.

Care and pruning

Barberries require very little fertiliser; occasionally, a lime-rich fertiliser once a year is sufficient. They tolerate pruning well and will sprout again even from old wood. Young plants should be cut back by about a third before planting to encourage bushy growth. For hedges, annual pruning in late winter (February/March) or autumn is recommended to maintain shape and density. Gloves must be worn when cutting due to the thorns. Cuttings should not be composted as the thorns will cause problems.

Uses of barberry

• Culinary: The sour berries are used fresh or dried in jams, jellies, juices and as a spice (e.g. in Oriental cuisine for rice dishes).
• Medical: Traditionally, berries and roots are used to treat lung, liver and spleen disorders. The active ingredient berberine has an antibacterial effect and can lower blood sugar levels. Barberry is also frequently used in food supplements . Both the berries and the root bark can be used for medicinal purposes. However, the medicinal properties of the different parts of the plant vary greatly. One could almost think that they are two different medicinal plants. The fruits contain vitamin C and substances typical of fruit, such as fruit acids. The root bark mainly contains alkaloids (e.g. berberine) and tannic acid.
• Colouring: The bark and roots were formerly used to dye textiles, leather and wood yellow.