Common Name: Butterfly Pea

General Information

Butterfly pea is a short-lived, herbaceous, perennial climbing, scrambling or trailing herb with a strong woody rootstock. It produces slender new annual stems that grow up to 3 metres long from the woody base each year. The stems do not root at the nodes[].
The plant is harvested from the wild as a food, medicine and dye. It has also long been cultivated, as a medicinal and dye plant; an ornamental for its showy flowering display; and as a soil improver in plantations[].

Known Hazards

None known

Botanical References

Range

Pantropical.

Habitat

It occurs in grassland, open woodland, bush, riverine vegetation, and disturbed places throughout its natural range[].

Properties

Edibility Rating
Medicinal Rating
Other Uses Rating
Habit	Deciduous Perennial
Height	3.00 m
Growth Rate	Fast
Pollinators	Insects
Self-fertile	No
Cultivation Status	Cultivated, Ornamental, Wild

Cultivation Details

Butterfly pea is essentially a plant of the humid and subhumid tropical lowlands at elevations from sea level to around 1,600 metres[]. It is also grown as an annual in warm temperate areas[]. It grows best in areas with an annual rainfall in the region of 1,500mm, but it has a reputation for drought tolerance in the seasonally dry tropics (with 500 - 900 mm annual rainfall) and can probably survive with as little as 400mm annual rainfall[]. Its annual mean temperature range is 19 - 28°c and it has survived moderate frost damage in the subtropics (at a latitude of 26°S)[].
Plants can succeed on a variety of soils as long as they are well-drained, but prefer a fertile, friable soil, growing poorly on infertile sandy soils if they not fertilized[]. It does well on heavy clay soils[]. Prefers a position in full sun[]. It succeeds within a pH range of 5.5 - 8.9[].
Butterfly pea is one of the few herbaceous legumes well adapted to heavy clay soils in the subhumid to semi-arid tropics and the only one with potential in irrigated pasture mixtures on these soils[].
Early growth of the plant from seed is rapid in warm moist conditions. Growth of established plants is mostly from the apices of the main axis and axillary branches; very few new shoots arise from ground level[].
Growth is more or less continuous in the humid tropics, or with irrigation in other hot regions. Individual plants may live for several years and grow into large vines if undisturbed[].
In the seasonally dry tropics and in cool regions, growth is limited by lack of moisture or low temperatures. Leaves are shed in response to these stresses and top growth may be killed by frost or fire. However, recovery during the following growing season is usually good[]
Butterfly pea competes fairly well with weeds once established and can cover the ground in 4 - 6 weeks when sown at a population of 4 plants per square metre. Establishment may be a problem on fertile soils if sown with a vigorous companion grass or oversown into an existing pasture. It combines better with tussock than stoloniferous grasses in mixed pastures. The location of its growing points at the ends of the main branches makes it susceptible to frequent low cutting as well as to continuous heavy grazing[].
Flowers are cleistogamous but a small level of outcrossing occurs. Time to flowering can range from 7 - 11 weeks. Subsequent flowering flushes overlap pod maturation from the previous flush, and they continue throughout the year in frost-free regions. At higher latitudes in the tropics, there is usually a peak at the end of the wet season and again at the end of the cool season, if moisture is available. Pods mature in 8 - 10 weeks after flowering and shatter readily once fully dry. There is considerable variation in the size of flowers and leaflets[].
The plant is propagated by seed and readily self- propagates and spreads under favourable conditions by seed thrown vigorously from the dehiscing dry pods. Seed is also spread in cattle dung[].Inoculation of butterfly pea seed with rhizobia is not usually necessary; but, if it is required, broad spectrum cowpea inoculum should be used[].
This species has a symbiotic relationship with certain soil bacteria, these bacteria form nodules on the roots and fix atmospheric nitrogen. Some of this nitrogen is utilized by the growing plant but some can also be used by other plants growing nearby[].

Edible Uses

The young pods are eaten as a vegetable[, , ].

The flowers are used to give a blue tinge to rice cakes and boiled rice[, ].

Young leaves - cooked and used as a vegetable[]. The leaves can also be used to colour food[].

Medicinal

The flowers are mixed with water in a preparation used to treat eye problems[].

The powdered, ripe seeds are aperient and purgative[, ].

The roots are bitter, powerfully cathartic, diuretic and purgative[, ].

The rootbark is diuretic and laxative[].

The plant is used in the treatment of snakebites[].

The seeds contain a fixed oil, a bitter resinous principle and tannins[].
The rootbark contains tannins[].

Agroforestry Uses:

Butterfly pea has a reputation as a potential fodder plant, hay or cover crop. It has been extensively tested as such, especially in the subhumid to semi-arid tropics. It has never been used in extensive areas, although it is used by smallholders. It is used as a cover crop in coconut in southern India and in rubber in Malaysia[].
A fast-growing plant, it provides good ground cover[].

Other Uses

The leaves and flowers are used as a dye[].

The seeds and bark are a source of tannins[].

Propagation

Seed - hand-harvested seed often remains hard-seeded for a long time and requires scarification prior to sowing. Mechanical abrasion, hot water or sulphuric acid can be used to break this dormancy. The seed is normally sown from the beginning until the middle of the wet season at rates of (1-)3 - 5 kg/ha in well-prepared seed-beds with seed placement 1.5 - 4 cm deep and lightly covered[]. Higher rates (5 - 8 kg/ha) may be required when sowing pastures in rough conditions[].
Germination is epigeal; the radicle emerges within 48 - 72 hours and seedlings emerge in 3 - 6 days, depending on planting depth[].

Add a Comment:

If you have any useful information about this plant, please leave a comment. Comments have to be approved before they are shown here.

Name:

Email(Private):

Message:

Captcha: a square has how many sides?