Common Name:

General Information

Trachyspermum ammi is an erect, aromatic, branched annual herb growing from 60 - 160cm tall[, ].
The plant is often cultivated, especially in southern Asia, for its seed which is used as a spice[, ]. It also has a wide range of medicinal applications.

Known Hazards

None known

Botanical References

,

Range

Asia - Iraq, Iran, Turkmenistan, Uzbekistan, Afghanistan, Pakistan, northern India, Nepal, Bangladesh, Myanmae

Habitat

Damp ground[].

Properties

Edibility Rating
Medicinal Rating
Other Uses Rating
Habit	Annual
Height	0.60 m
Pollinators	Bees
Self-fertile	Yes
Cultivation Status	Cultivated

Cultivation Details

Ajowan is a plant mainly of temperate areas with hot summers, though it can also be grown in the tropics and subtropics, where it is cultivated at elevations from near sea level up to 2,200 metres. It grows best in areas where annual daytime temperatures are within the range 16 - 24°c, but can tolerate 10 - 30°c[]. It prefers a mean annual rainfall in the range 800 - 1,000mm, but tolerates 700 - 1,100mm[].
Requires a moist soil in a sunny position[]. Prefers loamy soils that are not too heavy, though it can be grown on all types of soils[]. Wet-rice-growing soils are considered unsuitable, however, as they promote vegetative development at the cost of flowering[]. Prefers a pH in the range 6.5 - 7.5, tolerating 6 - 8[].
Flowering commences 2 - 4 months after sowing, and the seeds are ripe 2 months later[]. About70 - 80% of the crop is cross-pollinated, and pollination is primarily done by bees[].
As the plants are widely branched, flowering occurs unevenly, thus seeds mature unevenly, which makes them difficult to harvest[].
The seeds are often harvested before they are fully ripe, to prevent loss due to shattering[]. The essential oil quality of these fruits is considered the same as that of the ripe fruits[].
In India, yields of traditionally grown Ajowan are higher under dry rain-fed conditions than under irrigation, and amount to about 225 kg/ha of fruits. Improved cultivars may give yields of 1.2 - 2.2 tonnes/ha and in 1997 an improved cultivar yielded 82 kg/ha essential oil[].
There are some named varieties[].

Edible Uses

The pungently aromatic fruits are about 2cm long[]. The pungent flavour is said to be a combination of aniseed and oregano with a hint of black pepper[]. They are widely used, especially in India, the Mediterranean and Ethiopia, as a flavouring in savoury dishes, including curries, pulses, breads and pastry snacks[, ]. The fruit is usually dried, then roasted and ground into a powder before being used as a spice[].

An essential oil can be extracted from the whole plant and from the seed[]. Sweeter than oil of thyme, it is used as a flavouring[].

Medicinal

Ajowan seed, and the essential oil it contains, has a long history of medicinal use throughout its range, and the plant often cultivated in other areas[]. In India, the essential oil is known as 'ajowan oil', and enters into the Indian Pharmacopoeia[].
Considerable research has been carried out into the medicinal properties of the plant, and in particular the essential oil thymol that it contains.
Thymol, the main constituent of the essential oil, is strongly antiseptic, whilst the entire essential oil from the seed shows strong antibacterial activity against many gram-positive and gram-negative bacteria. It also showed long-term antifungal activity against a range of storage and soil-borne fungi[]. Thymol has also shown significant dose-dependent molluscicidal, nematicidal and larvicidal effects[].
The essential oil has been shown to have vasodilatory and hypotensive activity, producing a dose-dependent reduction in blood pressure and heart rate[]. In addition, it has shown effective anti-oxidant activity[].

The seed, and especially the essential oil in the seed, is strongly antiseptic, antispasmodic, aromatic, bitter, carminative, diaphoretic, digestive, diuretic, expectorant and tonic[, ]. It is used internally in the treatment of colds, coughs, influenza, asthma, diarrhoea, cholera, colic, indigestion, wind, oedema, arthritis and rheumatism[, ].
The essential oil is considered strongly antiseptic and is used to remove internal parasites[].
The seed is harvested when fully ripe and either distilled for the essential oil or dried for later use[].
The seed contains about 4 - 6% essential oil, of which 45 - 55% is the strongly antiseptic essential oil 'thymol'[]. The essential oil is also added to cough medicines[].

The root is carminative and diuretic[].

Other Uses

The seeds contain 3 - 10% essential oil[]. Between 30 and 35% of the essential oil is thymol[], which is more commonly found in Thymus species[]. The essential oil is added to epoxy derivatives[]. It is used medicinally and in perfumes[].
The essential oil is a strong inhibitor for sprouting of potatoes stored at room temperature[].

A semi-drying oil is obtained from the seed[].It is used for technical purposes[].

Propagation

Seed - we have no information for this species, but suggest that you try sowing the seed in situ in mid spring. If this is not successful, then an earlier sowing in the greenhouse in early spring, planting out after the last expected frosts might be better[]. It is quite possible that this species will not like to be transplanted, so either sow 4 - 5 seeds per pot, or sow in a tray and transplant to individual pots as soon as the seedlings are big enough to handle[].