Common Name: Lentil

General Information

Lens culinaris is a much-branched, erect, bushy, annual plant growing 30 - 80cm tall[].
Lentil is one of the oldest pulse crops and is of ancient cultivation in western Asia, Egypt and southern Europe. It probably originated in western Asia, from where it eventually spread throughout temperate and subtropical regions of the world and into the higher elevations in tropical areas. The earliest records of it being used date back to 11,000 BC in Ancient Greece, though it was another 5,000 years before it was being cultivated regularly. A very important food plant, its nutritious seed has become a staple food for many[, ].

Known Hazards

None known

Botanical References

Range

Original habitat is obscure, possibly the Mediterranean

Habitat

Not known in the wild.

Properties

Edibility Rating
Medicinal Rating
Other Uses Rating
Habit	Annual
Height	0.45 m
Pollinators	Cleistogamous, Insects
Self-fertile	Yes
Cultivation Status	Cultivated

Cultivation Details

Lentils can be cultivated from the temperate zone to the tropics, so long as there is a growing season of 4 months or more with a fairly dry period as the seed is ripening. In the tropics it can be grown at elevations up to 3,800 metres[]. It grows best in areas where annual daytime temperatures are within the range 15 - 29°c, but can tolerate 5 - 32°c[]. The plants are much hardier than is commonly supposed and there is at least one cultivar, called 'WH2040', that can withstand temperatures as low as -23°c in the seedling stage[]. The plant prefers a mean annual rainfall in the range 600 - 1,000mm, but tolerates 250 - 2,500mm[]. Dry conditions must prevail just prior to, and at, harvest time[].
An easily grown plant[], it prefers a sandy soil in a warm sunny sheltered position[, , ]. Another report says that it does best on clay[]. The plant can grow well on many soil types, so long as they are well-drained[]. It produces most seed when grown on poorer soils, richer soils tending to favour vegetative growth at the expense of flowering[, ]. Prefers a pH in the range 5.5 - 7.5, tolerating 4.5 - 8.2[].
There are several cultivars that are suitable for growing in temperate climates. 'WH2040', can withstand temperatures as low as -23°c in the seedling stage[]. 'Chilean' is a low-growing plant that can be grown in the winter in areas where winter vegetables can be grown[]. 'HarLen' tolerates temperatures down to -10°c and performs very well in garden situations[].
Flowering usually starts 6 - 7 weeks after sowing the seed. Early maturing cultivars can produce a seed crop in 70 - 120 days, late cultivars take 120 - 130 days[, ].
Lentils are harvested when the pods turn yellow-brown and the lower ones are still firm. Further delay may lead to shattering. In many areas the plant is cut down manually to ground level and left to dry for about 10 days, before being threshed and winnowed. Alternatively, for instance in Ethiopia, lentils are harvested by hand-pulling the plants, after which they are left in the field to dry to a seed moisture content of 12 - 13%[].
The common yield of seed under dry conditions is about 340 - 670 kilos per hectare, increasing to between 900 - 1,700 kilos at more favourable sites[]. In some areas yields of 3 - 4 tonnes per hectare have been achieved[].
There are many named varieties[, ].
Lentils are very beneficial to grow as part of a rotation on the farm or garden. They have 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 and, if the roots are left in the ground when the seeds are harvested, this will provide a source of nitrogen for the next crop[].

Edible Uses

Seed - cooked or sprouted and then eaten raw or cooked[, ]. A very nutritious food[, ], the seeds can be cooked on their own or added to soups, stews etc[]. The seed can be soaked for 12 hours in warm water and then allowed to sprout for about 5 days[]. They have a crunchy, fresh flavour[]. Lentils are more digestible than many legumes[]. The dried seed can also be ground into a powder and used with cereal flours in making bread etc[], this greatly enhances the value of the protein in the bread. The whole seed is roasted, then salted and eaten as a snack[]. The seed stores better if it is left in its husk[].

Young seedpods - used fresh or cooked like green beans[, , ].

Medicinal

The seeds are mucilaginous and laxative[]. They are considered to be useful in the treatment of constipation and other intestinal affections[, ].
Made into a paste, the seeds are a useful cleansing poultice, applied to foul and indolent ulcers[, ].

Agroforestry Uses:

The plant can be used as a green manure[].
Lentils are mainly grown as a sole crop, but they are sometimes mixed with other crops, e.g. in India with barley, mustard or castor[].

Other Uses

The seeds are a source of starch for the textile and printing industries[, ].

The plant remains, after the seed has been harvested, can be used as a fuel[].

Propagation

Seed - sow early mid spring in situ[]. Some cultivars are probably suitable for sowing outdoors in the autumn, at least in the milder parts of the temperate zone[].
A dormancy period of 4 - 6 weeks after harvest is common, and some cultivars have been found to be responsive to vernalization[299. The minimum temperature for germination is 15°c and the optimum temperature 18 - 21°c; temperatures above 27°c are harmful. At optimum temperatures, the seeds germinate in 5 - 6 days[].
Seeds can remain viable for more than 5 years under cool and dry storage conditions[]