Culture
This annual is typically grown in home gardens for culinary use as a lettuce-like salad green. It thrives in rich moist soils in full sun to part shade. It is best grown during the cooler spring and fall months of the year rather than in the heat of the summer. After last spring frost date, sow seeds in the garden a few inches apart in rows about 18” apart, with seedlings later thinned to a spacing of about 12”. In the alternative, seeds may be started indoors in containers prior to last spring frost date for later transplanting outdoors. Leaves must be harvested when young and tender. Leaf flavor becomes strong and often bitter as the leaves mature. A second crop can be planted in late summer for harvest before fall frost. Although this annual may self-seed in the garden, it is usually recommended that seed be purchased rather than harvested from garden plants. In St. Louis, seeds typically germinate in May with leaves harvested in early summer. By contrast, this plant also grows as a winter annual, albeit sometimes an invasive one, in some other parts of the U.S. such as the deserts of Arizona where seeds typically germinate in the wild after fall rains for growth over winter.
Noteworthy Characteristics
Eruca vesicaria, commonly known as by a number of common names including arugula, garden rocket, rocket salad, roka, roquette, rucola or rugula, is a Eurasian annual herb of the mustard family. It was first cultivated by ancient Greeks and Romans. It continues to be widely cultivated in Europe today, but has also been introduced into many other parts of the world including much of North America where it has become not only a treasured culinary plant, but also, in some cases, an invasive garden escapee and self-seeder. It typically naturalizes in disturbed habitats, fields and meadows.
Plants typically grow to 10-24” tall. Irregular, pinnately-lobed, basal leaves, each with 4 to 10 small lateral lobes and a large terminal lobe, appear in rosettes. Uppermost stem leaves are entire and smaller. Four-petalled flowers (to 1” long) bloom in corymbs. Each flower has a pale yellow corolla, yellow stamens, and dark brown or purple veins. Fruit (to 1.5” long) is a seeded, prominently-beaked pod.
Leaves should only be harvested when young and tender. Older leaves become bitter and lose significant culinary quality as they mature. Young leaves lack bitterness and are typically eaten raw, adding a peppery, some say nutty, mustard-like flavor to a variety of food dishes including salads, sandwiches, egg dishes, sauces, soups or stir fries. Notwithstanding its culinary virtues, this plant is also extensively cultivated in central and western Asia for its seed oil which is used as a lubricant and illuminant in pickling.
Subsp. sativa from Latin means cultivated in probable reference to the historical designation of this subspecies as a salad plant for cultivation in home gardens.
Some authors include this subspecies in with the species and others elevate it to its own species, Eruca sativa.
Genus name probably comes from the Latin eructo meaning to eruct or belch in reference to the strong, spicy, sometimes bitter taste of mature plant leaves
Specific epithet comes from the Latin word vesica meaning bladder in reference to the inflated seed pods.
Problems
No serious insect or disease problems. Flea beetles can be troublesome.
Uses
Herb or vegetable commonly used as a lettuce-like food flavoring.