ORACH, OR ARACH: A genus of the monoeica order, belonging to the polygamia-class of plants; and, in the natural method, ranking under the 12th order, Holoraceae. The calyx of the hermaphrodite flower has five leaves; there is no corolla; the stamens are five, and the style is bifid; the seed is one, and depressed.

Species. 1. The hortensis, or garden orach, was formerly cultivated in gardens, and used as a substitute for spinach, to which it is still preferred by some, tho' in general it is disliked by the English; however, it still maintains its credit in France, as also in the northern parts of England. There are three or four varieties of this plant, whose only difference is their colour; one is a deep green, another a dark purple, and a third with green leaves and purple-borders. 2. The halimus, or broad-leaved orach, was formerly cultivated in gardens as a shrub, by some formed into hedges, and constantly sheared to keep them thick; but this is a purpose to which it is by no means adapted, as the shoots grow so vigorous, that it is impossible to keep the hedge in any tolerable order; and, what is worse, in severe winters the plants are often destroyed. 3. The petulacoides, or shrubby sea-orach, grows wild by the sea-side in many places of Britain. It is a low under-shrub, seldom rising above two feet and a half, or at most three feet high; but becomes very bushy. This may have a place in gardens among other low shrubs, where it will make a pretty diversity. Besides these, nine other species are enumerated by botanical writers, but the abovementioned are the most remarkable.

Culture, &c. The first sort is annual, so must be propagated by seeds. These are to be sown at Michaelmas, soon after the seeds are ripe. The plants require no other culture than to be kept free from weeds, to hoe them when they are about an inch high, and to cut them down when they are too thick, so as to leave them about four inches asunder. When these plants are sown in a rich soil, and allowed a good distance from each other, the leaves will grow very large, and in this their goodness consists. This must be eaten whilst it is young; for when old, the leaves become tough, and are good for nothing. This species is an article of the materia medica; a decoction of the leaves is recommended in coliciveness, where the patient is of a hot bilious disposition.—The second sort may be propagated by cuttings. These are to be planted in any of the summer-months, in a shady border; where they will soon take root, and be fit against the following Michaelmas to transplant into those places where they are to remain.—The third sort requires very little culture. It may be also propagated from cuttings, and is to be planted in a poor gravelly soil.