Common Name: Anu

General Information

Anu is a perennial climbing plant, producing annual, twining stems from a tuberous rootstock. The stems can be 2 metres long, they trail over the ground or into the surrounding vegetation, supporting themselves by twisting their leaf stalks around the other plants[].
Long cultivated in the Andes for its edible root, there are many named varieties[, , , , ]. The plant is often grown as an ornamental.

Known Hazards

None known

Botanical References

Range

S. America - northwest Argentina, Bolivia, Peru, Ecuador, Colombia

Habitat

Mountain slopes and valleys[]. Moist wooded scrubby areas around 3000 metres in Peru and Ecuador[].

Properties

Edibility Rating
Medicinal Rating
Other Uses Rating
Habit	Perennial Climber
Height	2.00 m
Growth Rate	Medium
Pollinators	Insects
Cultivation Status	Cultivated, Ornamental, Wild

Cultivation Details

Anu is a plant of higher elevations in the tropics, where it is found at elevations from 3,000 - 4,300 metres. It can be cultivated at lower elevations in the subtropics and warmer parts of the temperate zone. It grows best in areas where annual daytime temperatures are within the range 12 - 20°c, but can tolerate 4 - 24°c[]. When dormant, the plant can survive temperatures down to about -2°c, but young growth can be severely damaged at 0°c[]. It prefers a mean annual rainfall in the range 1,000 - 1,200mm, but tolerates 700 - 1,600mm[]. Anu is sensitive to the number of hours of daylight in a day and most forms will not flower or form new tubers when the length of daylight is more than 12 hours[].
Requires a well-drained lime-free soil in a warm sunny position[, , ]. Grows best with its roots in the shade and top growth in the sun[]. Prefers a turfy loam or a sandy peaty soil[]. Prefers a pH in the range 6 - 7, tolerating 5.3 - 7.5[, ]. Plants can become dormant in hot dry summers[].
A potentially very high-yielding species, individual plants can produce up to 4 kilos of tubers - yields of 50 tonnes per hectare are possible[].
The variety 'Ken Aslet', is daylight neutral, it flowers freely and produces larger tubers than the species[, , ].
The tubers are formed very near the surface of the soil[].
The caterpillars of the cabbage white butterfly can be a nuisance and often cause considerable damage to the leaves[].

Edible Uses

Tubers - cooked[, ]. A peppery flavour, it is rather unpleasant to many tastes[, , ]. The flavour can be improved somewhat by freezing the tubers after they have been cooked, they are then considered to be a delicacy by many people[]. We have also noticed an improvement in the flavour if the tubers are harvested after they have been frosted, though if the frost is too heavy they can damage the tubers[]. Other reports suggest half-drying the tubers before use[, , , ]. The tubers can be up to 10cm long and 5cm thick[]. They are high in vitamin C[]. The dried tuber contains up to 16% protein[].

Leaves - raw or cooked as a vegetable[, ].

Flowers - raw[, ].

Medicinal

The tuber is considered to be an anaphrodisiac in the Andes, reducing sexual desire. Many men, therefore, refuse to eat it, whilst recommending it for use by women![]. Clinical trials have indicated a reduction of up to 45% in some male hormones when the tuber forms a considerable part of the diet, but no loss in fertility has been observed[].

Other Uses

The growing plant is very resistant to diseases and insects, it contains nematocidal, bactericidal and insecticidal compounds[].

Propagation

Seed - sow early spring in a greenhouse. Prick the seedlings out into individual pots once they are large enough to handle and grow them on in the greenhouse for their first winter. Plant out in late spring or early summer, after the last expected frosts. So far we have been unable to obtain seed from plants grown in this country.
Division of the tubers in the autumn or spring. In cold winter areas the tubers can be harvested in the autumn after top-growth has died down and they can then be stored in a cool frost-free position until planting them out in the spring.
Cuttings of basal stems in the spring[]. Pot them up into individual pots and place them in light shade in a frame until they are established. Plant out in early summer.