Common Name: Maca

General Information

Lepidium meyenii is a herbaceous perennial plant growing from a succulent tuberous rootstock. It produces a basal roette of 12 - 20 leaves and short, decumbent flowering stems 12 - 20cm long[].
Maca has a long history of use as a vegetable and medicine in the Andes, being often cultivated at higher elevations and used there as a staple food. It is sold in local markets and the dried, powdered root has become a popular healthfood supplement and cosmetic ingredient in many countries. This species is probably grown at higher elevations than any other cultivated food crop[, ].

Known Hazards

None known

Botanical References

Range

S. America - Andes of Peru, Bolivia, northern Argentina and Chile.

Habitat

Barren steppes, tundra and alpine plains, usually in limestone and clay soils, at elevations from 3,800 - 4,800 metres[].

Properties

Edibility Rating
Medicinal Rating
Habit	Perennial
Height	0.05 m
Pollinators	Insects
Self-fertile	Yes
Cultivation Status	Cultivated

Cultivation Details

Maca grows at high altitudes in the Andes in an inhospitable region of intense sunlight, violent winds and below freezing weather. With its extreme temperatures and poor rocky soil, the area rates among the world's worst farmland, yet over the centuries, Maca has learned to flourish under these conditions[]. It grows best in areas where annual daytime temperatures are within the range 12 - 18°c, but can tolerate 3 - 22°c[]. Plants grow in areas where frosts are common throughout the growing season and they are said to tolerate temperatures down to at least -10°, perhaps to -20°c if given a good mulch[]. It prefers a mean annual rainfall in the range 600 - 800mm, but tolerates 500 - 1,000mm[].
Requires a sunny position[]. Prefers a well-drained soil with a medium to heavy texture[]. Prefers a pH in the range 6.5 - 7.5, tolerating 6 - 8.5[]
The plant is said to deplete the soil in which it is grown. In S. America it is grown traditionally on a 10 year rotation, leaving the fields fallow for the next nine years to recover before their next crop[]. It is most likely that the problem lies with the nutrient-poor and fragile soils that the plant is usually grown in, rather than the greed of the plant[].
There are some named forms[]. The roots are usually harvested 6 - 7 months after sowing the seed, though they can take 9 months to mature[]. Yields of 20 tonnes per hectare are possible[].
Plants are self-fertile[]. They are also quite possibly allelopathic (inhibiting the growth of nearby plants)[].

Edible Uses

Root - cooked. Sweet and pleasantly flavoured[]. They can be slowly baked[]. They can be roasted, dried and boiled or used for making juices, porridges, jams etc[]. Traditionally, after being dried they are cooked in water to make a sweet aromatic porridge that is called 'mazamorra' in S. America[]. The nutritional value of dried Maca root is high, resembling cereal grains such as maize, rice and wheat. It has 59% carbohydrates, 10.2% protein, 8.5% fibre and 2.2% lipids.(263) It has a large amount of essential amino acids and higher levels of iron and calcium than potatoes.(263) Maca contains important amounts of fatty acids including linolenic, palmitic and oleic acids. It is rich in sterols and has a high mineral content as well[]. The root resembles a small pear in both size and shape and is up to 8cm in diameter[, ]. The dried root contains about 13 - 16% protein and is rich in essential amino acids[]. The fresh root is unusually high in iodine and iron[]. The root does also contain small amounts of alkaloids, tannin and saponins[]. The dried roots store well, 7 year old roots still had 9 - 10% protein[]. Dried roots are brown, soft and sweet with a musky flavour, they retain their flavour for at least 2 years.

Young leaves[, ] - raw or cooked[, ]. A hot cress-like flavour.

Medicinal

Maca is a little known herbal remedy and high energy food. It is growing in popularity due to its energizing effects, fertility enhancement and aphrodisiac qualities. Other traditional uses include increasing energy, stamina and endurance in athletes, promoting mental clarity, treating male impotence, and helping with menstrual irregularities and female hormonal imbalances including menopause and chronic fatigue syndrome[].The roots are antifatigue, aphrodisiac, nutritive, immunostimulant, steroidal and tonic[].

Maca, as with all crucifers, contains glucosinolates and isothiocyanates which have been shown to exhibit anticarcinogenicity by blocking formation of endogenous or exogenous carcinogens and so preventing initiation of carcinogenesis[]. Naturally occurring and synthetic isothiocyanates are among the most effective chemopreventive agents known[]. A wide variety of isothiocyanates prevent cancer of various tissues including the rat lung, mammary gland, oesophagus, liver, small intestine, colon, and bladder[]. Non-published data suggests Maca has this same effect. Surprisingly, there is no apparent traditional use of Maca in the treatment of cancer[].

In traditional Peruvian herbal medicine, Maca is used as an immunostimulant and in the treatment of anaemia, tuberculosis, menstrual disorders, menopause symptoms, stomach cancer, sterility and other reproductive and sexual disorders as well as to enhance memory[].

A chemical analysis conducted in 1981 showed the presence of biologically active aromatic isothiocyanates, especially p-methoxybenzyl isothiocyanate, which have reputed aphrodisiac properties[]. Initial analysis of Maca indicate that the effects on fertility are a result of the glucosinolates. Alkaloids are also present, but have not yet been quantified.(263).

There are reports that this plant can cure many problems of infertility[].

Other Uses

An extract of the whole plant is used as an ingredient in commercial cosmetic preparations as a skin conditioner[].
An extract of the roots is used as an ingredient in commercial cosmetic preparations as a skin conditioner[].
The dried and powdered root is used as an ingredient in commercial cosmetic preparations as a humectant[].

Propagation

Seed - traditionally it is sown in situ. If growing a small quantity, or in areas outside its native range, then it could be worthwhile sowing the seed in early spring in a cold frame. Either transplant the seedlings into open ground when they have produced 4 - 6 true leaves, or prick them out into individual pots as soon as they are large enough to handle and then plant them out in early summer.