Lawsonia inermis, also known as hina, the henna tree, the mignonette tree, and the Egyptian privet, is a flowering plant and one of the only two species of the genus Lawsonia, with the other being Lawsonia odorata. It is used as a traditional medicinal plant. The species is named after the Scottish physician Isaac Lawson, a good friend of Linnaeus.

Description

Henna is a tall shrub or small tree, standing 1.8 to 7.6 m. It is glabrous and multi-branched, with spine-tipped branchlets. The leaves grow opposite each other on the stem. They are glabrous, sub-sessile, elliptical, and lanceolate (long and wider in the middle; average dimensions are 1.5–5.0 cm x 0.5–2 cm or .6–2 in x 0.2–0.8 in), acuminate (tapering to a long point), and have depressed veins on the dorsal surface. Henna flowers have four sepals and a 2 mm calyx tube, with 3 mm spread lobes. Its petals are ovate, with white or red stamens found in pairs on the rim of the calyx tube. The ovary is four-celled, 5 mm long, and erect. Henna fruits are small, brownish capsules, 4 – in diameter, with 32–49 seeds per fruit, and open irregularly into four splits.

Distribution and habitat

The henna plant is native to northern Africa, Asia and northern Australia, in semi-arid zones and tropical areas.

Cultivation

It produces the most dye when grown in temperatures between 35 and 45 °C. During the onset of precipitation intervals, the plant grows rapidly, putting out new shoots. Growth subsequently slows. The leaves gradually yellow and fall during prolonged dry or cool intervals. It does not thrive where minimum temperatures are below 11 °C. Temperatures below 5 °C will kill the henna plant.

Dye

Its dried leaves are the source of the dye henna used to dye skin, hair and fingernails, as well as fabrics including silk, wool and leather.

Image gallery

<Gallery> File:Lawsonia inermis henna Egyptian privet Vijayanrajapuram 01.jpg|Henna flowers File:Lawsonia inermis henna Egyptian privet Vijayanrajapuram 02.jpg|Henna flowers File:Lawsonia inermis henna Egyptian privet Vijayanrajapuram 05.jpg|Henna flowers- night view File:Lawsonia inermis henna Egyptian privet Vijayanrajapuram 07.jpg|Henna fruits </Gallery>