== Origin and geographic distribution ==
Lablab is believed to be native to India, South-East Asia or Africa. It is naturalized and cultivated in the tropics and subtropics, particularly in India, South-East Asia, Egypt and the Sudan.
== Uses ==
In South-East Asia, lablab is popular as a vegetable, the young fruits eaten boiled like common beans or used in curries, immature green seeds are eaten boiled or roasted, leaves, young shoots and inflorescences are eaten boiled. In other parts of Asia, lablab is predominantly used as a pulse, often as dhal. Sometimes sprouted seeds are sun-dried and stored
to use as vegetable. Lablab is used also as fodder, hay, silage, green manure and cover crop.
== Properties ==
Per 100 g edible portion of immature pods contain: water 82.4 g, protein 4.5 g, fat 0.1 g, carbohydrates 10.0 g, fibre 2.0 g, ash 1.0 g. The energy content averages 1260 kJ/100 g. The content of protein in mature seeds is normally 21-29 g/100 g. Fully ripe Indian seeds contain per 100 g edible portion: water 9.6 g, protein 24.9 g, fat 0.8 g, carbohydrates 60.1 g, fibre 1.4 g, ash 3.2 g. The energy content averages 1403 kJ/100 g. The presence of a cyanogenic glycoside has been reported in certain cultivars. Seed weight varies between 25 and 50 g/100 seeds.
== Description ==
*A bushy or a climbing and branching, pubescent herbaceous perennial, often grown as an annual, up to 6 m tall, with a well developed tap-root with many laterals and well developed adventitious roots.
*Leaves alternate, trifoliolate; leaflets broadly ovate, 5-15 cm × 4-15 cm, entire, subglabrous or soft hairy.
*Inflorescences stiff axillary racemes with many flowers; peduncle 4-23 cm long, often compressed, glabrescent; rachis 2-24 cm long; flowers arising 1-5 together from tubercles on rachis
*Pedicels short, square, sparsely pubescent; flowers white, pink, red or purple; stamens diadelphous (9 + 1); ovary sessile, 10 mm long, finely pubescent; style abruptly upturned, 8 mm long; stigma capitate, glandular.
*Pods variable in shape and colour, flat or inflated, 5-20 cm × 1-5 cm, straight or curved, usually with 3-6 ovoid seeds of varying colour and size.
== Growth and development ==
Germination is epigeal and normally takes 5 days. Seed remains viable for 2-3 years and
on average 85-95 % germinate. Growth period varies from 75 to 300 days. Improved cultivars start fruiting 60-65 days after sowing and continue for 90-100 days. Early-maturing cultivars that can be grown all year round produce pods 60 days after sowing and continue up to 120 days. Mature seeds are harvested 150-210 days after sowing, depending upon cultivar and time of sowing. In India, short-day cultivars start flowering 42-330 days after sowing, depending on the sowing date. The flowers are mainly cross-pollinated.
== Other botanical information ==
== Ecology ==
Lablab is a short-day plant. It requires high temperatures to grow well (18-30 °C). Minimum temperature for growth is 3 °C. Its frost tolerance is low; light frosts damage the leaves but do not kill the plants. It prefers rainfall at 750-2500 mm/year. Once established (2-3 months after sowing), lablab is drought-tolerant. It has a deep root system which can make use of residual soil moisture. It is reported to grow in areas with rainfall at 200-2500 mm/year. Plants do not tolerate standing brackish water or waterlogging. In India and Burma, the plants are often grown on exposed sandy river banks. Provided drainage is good, the plant is extremely tolerant of soil texture, growing in deep sands to heavy clays, pH ranging from 5-7.8. Lablab prefers the lower altitudes but is grown as a dry-land crop up to 2000 m in the tropics.
== Propagation ==
Propagation is by seed at 7-10 kg/ha, up to 5 cm deep in a preferably well prepared seed-bed. Lablab can establish itself after being broadcast into roughly ploughed land, if the seed is covered to some extent. As a field crop, lablab is usually sown in rows, either as a sole crop (rows 1 m apart) or intercropped with a cereal, e.g. with maize, rows 80 cm apart. In India, it is invariably grown with Eleusine coracana. Inoculation with cowpea- type Rhizobium strains is advised, if lablab has not been grown recently. Lablab is only grown by smallholders.
== Husbandry ==