Growing Lentils

Lentils are believed to have originated in central Asia, having been consumed since prehistoric times. They are one of the first foods to have ever been cultivated. Lentil seeds dating back 8000 years have been found at archeological sites in the Middle East.

Lentils were mentioned in the Bible both as the item that Jacob traded to Esau for his birthright and as a part of a bread that was made during the Babylonian captivity of the Jewish people.

For millennia, lentils have been traditionally been eaten with barley and wheat, three foodstuffs that originated in the same regions and spread throughout Africa and Europe during similar migrations and explorations of cultural tribes.

Before the 1st century AD, they were introduced into India, a country whose traditional cuisine still bestows high regard for the spiced lentil dish known as dal. In many Catholic countries, lentils have long been used as a staple food during Lent. Currently, Canada is the largest export producer of lentils in the world and Saskatchewan is the most important producing region in Canada.

Lentils are an easily grown annual plant taking the same time as peas to mature. Although they prefer a sandy soil in a warm sunny sheltered position, many believe that the plant produces most seed when grown on poorer soils. Some varieties are quite hardy even surviving the cooler  growing conditions of countries like Great Britain.

Lentil plants are slender, semi-erect annuals with compound leaves (4 to 7 pairs of leaflets) with a tendril at the tips. Plants normally range from 12 to 20 in. tall, the taller plants resulting from cool growing season temperatures, good moisture and good fertility. Plants can have single stems or many branches depending upon the population in the field.

Flowering begins on the lowest branches, gradually moving up the plant and continuing until harvest. Each flower produces a short pod containing one or two lens-shaped seeds. Flowers can be white, lilac or pale blue in color and are self-pollinated. At maturity plants tend to lodge because of their weak stems.

Lentils are slow to establish and produce limited vegetative growth and therefore sensitive to weed competition.  Weed control options for lentils are limited.  Selection of clean fields with histories of low weed pressure is paramount towards lessening the impacts of weeds.

The plants are short with finely divided leaves,  flowers of red, pink, purple or white and carry pods which contain two seeds.  The green varieties have green or tan seed coats and green cotyledons. The red lentils have tan or pink seeds coats, and pink or red cotyledons.

The pods are left on the plant until they are dry and shrivelled at which point they can be harvested and shelled. No other treatment is necessary. If seeds are still moist,  drying can be completed in the sun, oven or a dehydrator.

Lentil is adapted to all soil types, from sand to clay loam, if there is good internal drainage. Lentil does not tolerate flooded or waterlogged soils, and does best on deep, sandy loam soils high in phosphorus and potassium. Good drainage is required, because even short periods of exposure to waterlogged or flooded field conditions kill plants. A soil pH near 7.0 is best for lentil production.

Lentil should be sown in late April or early May, when soil temperatures are above 40 degrees F (10 C). Early seeding will increase the height and size of the plant at first bloom.  In most years, delayed planting after April lowers quality and seed yield.  The seeding depth should be 1.2 to 3 in (3 to 8 cm).

Because of the small seed size of some varieties, lentil cannot emerge if planted too deep or if the soil has crusted extensively. Lentil has hypogeal emergence, which means that the growing point emerges but the cotyledons remain in the soil.

Unless nodulated field pea or lentil has been grown recently on a field, the seed should be inoculated with Rhizobium leguminosarum just prior to planting (within 24 hours). Follow the instructions for inoculation, and protect treated seed from high temperatures and drying winds until planted. Various forms of inoculant are available, some of which can be placed in the furrow with the seed.

Good quality lentil seed does not need to be treated with insecticides or fungicides, because it germinates rapidly and seedlings emerge quickly. Seed treatment compounds can interfere with the nodulation process. Lentil is not very competitive (especially as seedlings) with many of the grasses and/or broadleaf weed species that infest farm fields, so weed control before planting and early in the growing season is critical.

A firm, smooth seedbed with most of the previous crop residue incorporated is best for lentil. Uneven surfaces, large clods, rocks or protruding crop residue can interfere with seed placement and complicate later swathing and combining.

Lentils should be harvested when plants begin to turn yellow and the lower pods become brown to yellow-brown in color. This will occur within several days and should be carefully watched, as pods can readily shatter. Lentil should be harvested when there is sufficient moisture to toughen the pods. Harvesting should not be done during hot, dry periods of the day.

One advantage of lentils over other legumes is that they do not require soaking. You can soak them for a few hours if you wish and this will reduce the cooking time by about half.

Before cooking with lentils it is advisable to rinse them in cold water and pick through them for any little stones which may be present.  When cooking lentils by themselves, in preparation for adding to a recipe or as an accompaniment, use 3 times the amount of water to lentils and avoid cooking with anything acidic, such as vinegar, as that retards the cooking process.

Lentils can be frozen but make sure you only partially cook them so that when they are defrosted and added to a recipe they retain some texture.