The taxonomy of the genus Eruca is very confused with different treatments varying in the names and numbers of accepted species. We are following the treatment of Lemmel C. & Attioui Z. in Eruca aurea Batt., The Saharan Rocket. How to put an end to the confusions within the genus Eruca?[] which sees the cultivated salad plant (Argula or Rocket) treated as the distinct species Eruca sativa, with five other species recognized[].

Common Name: Rocket

General Information

Eruca sativa is a fast-growing, erect, branched annual plant, producing a basal rosette of leaves followed by one or more flowering stems; it can grow up to 60cm tall.
This is the cultivated rocket, grown in gardens and on a larger scale as a source of salad leaves, medicines, essential and fixed oils. The plant has become fairly well known as a richly flavoured addition to salads and it is occasionally cultivated for its edible leaves and flowers, especially in the Mediterranean and in Sudan, but also on a small scale in a number of other countries.

Known Hazards

None known

Botanical References

,

Range

Europe - Mediterranean, through temperate western, central and eastern Asia to Mongolia and China

Habitat

Waste ground, fields, olive groves, stony hills, tracksides etc[].

Properties

Edibility Rating
Medicinal Rating
Other Uses Rating
Habit	Annual
Height	0.60 m
Growth Rate	Fast
Pollinators	Insects
Cultivation Status	Cultivated, Wild

Cultivation Details

Eruca sativa is a plant originally of the Mediterranean region, it can be cultivated from the temperate zone to the tropics. It grows best in areas where annual daytime temperatures are within the range 15 - 25°c, but can tolerate 8 - 29°c[]. It is tolerant of winter cold with temperatures dropping below freezing for short periods. It prefers a mean annual rainfall in the range 500 - 900mm, but tolerates 300 - 1,100mm[].
Succeeds in full sun, but prefers some shade from the hottest sun[]. A very easily grown and fast-maturing plant, it succeeds in most well-drained soils and conditions, though it prefers sandy and sandy loam soils[, ]. Prefers a pH in the range 7 - 8, tolerating 6 - 8.5[]. The plant grows best and is more productive in a moist, but not wet soil - once established, it is quite drought resistant[, ].
Plants can be ready for harvest within 40 days of sowing the seed[, , , ].
A good yield of leaves is 12 - 16 tonnes/ha, most of which is collected from the first harvest[].
High nitrogen levels in the soil can increase the yield of leaves by up to 50%[].
Plants usually self-sow freely if the ground is disturbed in some way, such as by hoeing[].
There are some named varieties. 'Rocket Improved' is less prone to bolting, though it still grows best in cooler weather[].
This species is normally untroubled by pests or diseases[].

Edible Uses

Young leaves - raw or cooked[, , , , ]. A distinct strongly spicy flavour[], the taste is best from fast, well-grown plants[]. A few leaves added to a salad are acceptable though the flavour is too strong for many tastes[]. Some people really like these leaves though most are not very keen[]. Older leaves that have become too hot to eat on their own can be pureed and added to soups etc[]. In the milder areas of Britain it is possible to produce edible leaves all year round from successional sowings, especially if the winter crop is given some protection[].

Flowers - raw[52}. A similar taste to the leaves, they make a nice garnish on the salad bowl[].

The seed yields a semi-drying oil[, , ]. Its use as a salad or cooking oil is limited because of its initial acridity; this acridity disappears after storing the oil for 6 months, it is then suitable for edible purposes[, , ] The oil can be used as a substitute for rapeseed oil[]. It contains 32% fat, 27% protein[]. It is known as 'jamba oil'[].

A mustard is obtained from the seed[, , ]. The strong flavour comes from an essential oil that is contained within the oil of the seed[]. The pungency of mustard develops when cold water is added to the ground-up seed - an enzyme (myrosin) acts on a glycoside (sinigrin) to produce a sulphur compound. The reaction takes 10 - 15 minutes. Mixing with hot water or vinegar, or adding salt, inhibits the enzyme and produces a mild bitter mustard[].

Medicinal

Rocket was at one time often used medicinally, though it is now seen mainly as a salad herb[].

The leaves are antiscorbutic, diuretic, rubefacient, stimulant and stomachic[, , ].

Eruca contains the glucosinolate methylsulphinylbutyl isothiocyanate which induces enzymes which have anticancer activity[].

The seed is rubefacient and stimulant[, ]. The powdered seed possesses antibacterial activity, but no alkaloids have been isolated[].

The oil from the seed is said to have aphrodisiac properties[, ]. The oil can be used for massage and for soothing the skin[].

Other Uses

The seed yields a semi-drying oil which is a substitute for rapeseed oil[]. It is rich in erucic acid[]. It produces very little soot when it burns and so it can also be used for lighting[]. Eruca seed oil is mainly used in industries as a lubricant, for soap-making, as an illuminating agent, in massaging, in medicines and in cooking as a salad oil[]. Erucic oil is sometimes used for adulterating rapeseed/mustard oil[]. High erucic acid (HEA) oil has special properties which include: High smoke and flash points, oiliness and stability at high temperatures, ability to remain fluid at low temperatures and durability[]. HEA oil is used to produce erucamide which is used as a slip additive in polythene and polypropylene, to reduce surface friction and prevent adhesion between film surfaces[]. HEA oil is also used in printing inks, lubricants and has a range of other applications[].

An essential oil from the leaves of Eruca sativa contains 67 volatile components, representing 96.52% of the oil. The oil is characterized by a high content of sulphur and nitrogen containing compounds[].

Propagation

Seed - sow outdoors in spring in situ. Germination is usually very quick and free. In order to obtain a continuous supply of edible leaves, successional sowings can be made every few weeks until mid August[]. A late summer/early autumn sowing can provide leaves in winter, though the plants might require some protection in very cold winters[].