Common Name: Great Burdock

General Information

Arctium lappa is a herbaceous, biennial plant that can grow up to 2 metres tall when flowering. The plant produces a rosette of basal leaves and a deep, stout taproot in its first year of growth, sending up a tall flowering stem in its second year.
Burdock is a very important medicinal herb in both Eastern and Western traditions and is also often used as a food. Commonly harvested from the wild, it is also often cultivated for medicinal use and, especially in Japan, for its edible root,
The plant has been spread through human agency to many temperate areas of the globe, including Australia and N. America.

Known Hazards

Care should be taken if harvesting the seed in any quantity since tiny hairs from the seeds can be inhaled and these are toxic[].

Botanical References

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Range

Europe - Norway to Spain, through most of Europe and temperate Asia to the Caucasus, Iraq, Afghanistan, India, Nepal and China

Habitat

Waste ground, preferring calcareous soils[], it is sometimes also found in meadows and woods[]. Near villages, roadsides, near rivers, wet and waste places, forest margins, thickets, valleys, slopes; at elevations from 700 - 3,500 metres[].

Properties

Weed Potential	Yes
Edibility Rating
Medicinal Rating
Other Uses Rating
Habit	Biennial
Height	1.50 m
Pollinators	Bees, Lepidoptera, Self
Self-fertile	Yes
Cultivation Status	Wild

Cultivation Details

The top growth dies back at temperatures a little above freezing, but the roots tolerate much lower temperatures[] and in most parts of the temperate zone when they are grown as a vegetable, the plants can be left in the ground all winter to be harvested as required.
Succeeds in most soils when grown in partial shade[]. Prefers a moist neutral to alkaline soil[] and a sunny position in a heavy soil[]. Plants are best grown in a light well-drained soil if the roots are required for culinary use[, ]. Tolerates a pH in the range 4.6 to 7.8.
Burdock is cultivated for its edible root in Japan, there are some named varieties[]. Spring-sown seed produces edible roots in late summer and autumn, whilst autumn sown crops mature in the following spring or early summer[].
Although the plants are quite large, it is best to grow them fairly close together (about 15cm apart, or in rows 30cm apart with the plants 5 - 8cm apart in the rows) since this encourages the development of long straight roots[].
The seed head has little hooked prickles and these attach themselves to the hairs or clothing of passing creatures and can thus be carried for some considerable distance from the parent plant[]. The plants usually self-sow freely[].
The flowers are very attractive to bees and butterflies[].

Edible Uses

Root - raw or cooked[, , , , ]. Very young roots can be eaten raw, but older roots are normally cooked[]. They can be up to 120cm long and 2.5cm wide at the top, but are best harvested when no more than 60cm long[]. Old and very long roots are apt to become woody at the core[]. Although it does not have much flavour the root can absorb other flavours[]. Young roots have a mild flavour, but this becomes stronger as the root gets older[]. The root is white but discolours rapidly when exposed to the air[]. Roots can be dried for later use[]. They contain about 2.5% protein, 0.14% fat, 14.5% carbohydrate, 1.17% ash[]. The root contains about 45% inulin[]. Inulin is a starch that cannot be digested by the human body, and thus passes straight through the digestive system. In some people this starch will cause fermentation in the gut, resulting in wind[]. Inulin can be converted into a sweetener that is suitable for diabetics to eat[].

Young leaves - raw or cooked[, , , ]. A mucilaginous texture[]. The leaves contain about 3.5% protein, 1.8% fat, 19.4% carbohydrate, 8.8% ash[].

Young stalks and branches - raw or cooked[, , , , ]. Used like asparagus or spinach[, ]. They taste best if the rind is removed[, ]. The leaf stalks can be parboiled and used as a substitute for cardoons[].

The pith of the flowering stem can be eaten raw in salads, boiled or made into confections[, ]. A delicate vegetable, somewhat like asparagus in flavour[].

The seeds can be sprouted and used like bean-sprouts[, , ].

Medicinal

Burdock is one of the foremost detoxifying herbs in both Chinese and Western herbal medicine[]. The dried root of one year old plants is the official herb, but the leaves and fruits can also be used[]. It is used to treat conditions caused by an 'overload' of toxins, such as throat and other infections, boils, rashes and other skin problems[]. The root is thought to be particularly good at helping to eliminate heavy metals from the body[].
The plant is also part of a North American formula called essiac which is a popular treatment for cancer. Its effectiveness has never been reliably proven or disproven since controlled studies have not been carried out. The other herbs included in the formula are Rumex acetosella, Ulmus rubra and Rheum palmatum[].

The plant is antibacterial, antifungal, carminative[, , , , ]. It has soothing, mucilaginous properties and is said to be one of the most certain cures for many types of skin diseases, burns, bruises etc[, ]. It is used in the treatment of herpes, eczema, acne, impetigo, ringworm, boils, bites etc[]. The plant can be taken internally as an infusion, or used externally as a wash[]. Use with caution[].

The roots of one-year old plants are harvested in mid-summer and dried. They are alterative, aperient, blood purifier, cholagogue, depurative, diaphoretic, diuretic and stomachic[, ].

The seed is alterative, antiphlogistic, depurative, diaphoretic and diuretic[]. Recent research has shown that seed extracts lower blood sugar levels[]. The seed is harvested in the summer and dried for later use[].
The crushed seed is poulticed onto bruises[]. The leaves are poulticed onto burns, ulcers and sores[].

The plant is used in homeopathy where it is very important in skin therapeutics, treating conditions such as eruptions on the head, face, and neck; pimples; acne; styes and ulcerations on the edge of the eyelids[].

Other Uses

The juice of the plant, when used as a friction, is said to have a stimulating action against baldness[].

This plant could certainly be utilized industrially, having an excellent fibre beneath the bark which often attains a length of 1 meter without a break[].

Propagation

Seed - best sown in situ in the autumn[]. The seed can also be sown in spring[]. Germination can be erratic, it is best to sow the seed in trays and plant out the young plants before the tap-root develops[]. Seed requires a minimum temperature of 10°c, but a temperature of 20 - 25°c is optimum[]. Germination rates can be improved by pre-soaking the seed for 12 hours or by scarification[]. They germinate best in the light[]. The autumn sowing should be made as late as possible because any plants with roots more than 3mm in diameter in the spring will quickly run to seed if cold temperatures are followed by daylengths longer than 12½ hours[].