Liquorice: A genus of the decandria order, belonging to the diadelphia clas of plants; and in the natural method ranking under the 32d order, Papilionaceae. The calyx is bilabiata; the upper lip tripartite, and the under one entire; the legumen ovate and comprisled. There are two species:

1. The glabra, or common liquorice, hath a long, thick, creeping root, striking several feet deep into the ground; upright, firm, herbaceous stalks annually, three or four feet high, garnished with winged leaves of four or five pair of oval lobes, terminated by an odd one; and from the axillas erect spikes of pale blue flowers in July, succeeded by short smooth pods. The root of this is the useful part, which is replete with a sweet, balsamic, pectoral juice, much used in all compositions for coughs and disorders of the stomach.

2. The echinata, or prickly-podded liquorice, is nearly like the common sort, only the seed-pods are prickly. Both these species are very hardy perennials; but the first is the sort commonly cultivated for use, its roots being fuller of juice and sweeter than the other. The roots are perennial; but the stalks rise in spring and decay in autumn.

Propagation and culture. Their propagation is effected by cuttings of the small roots issuing from the sides of the main ones near the surface of the earth, dividing them into lengths of six or eight inches, each having one or more good buds or eyes; and the proper season for procuring the sets for planting is any time in open weather from October till March, though from the middle of February till the middle of March is rather the most successful season for planting. An open situation is the most suitable for a plantation of these plants. Particular regard should also be had to the soil: it ought to be of a light loose temperature, and three or four feet deep if possible; for the roots of the liquorice will arrive at that depth and more, and the longer the roots the more valuable they are for sale by weight.

Having fixed on the ground, let it be trenched three spades deep, if the depth of proper soil will admit; then having your sets ready, proceed to plant them by line and dibble, planting the sets a foot distance in each row; putting them perpendicular into the ground, with the tops about an inch under the surface; and let the rows be a foot and a half asunder; though the London gardeners seldom allow more than twelve inches between row and row. These gardeners also sow a crop of onions on the same ground the first year; which, as the onions root but slender, and spread but little at top, may be done without any detriment to the liquorice, or to the onions, as it does not rise above ten or twelve inches high the first summer; observing to keep the ground clean from weeds during that season by hoeing. If there is a crop of onions, use the small hoe, cutting out the onions to four or five inches distance, clearing away such as grow immediately close to the liquorice plants; and when the onions are gathered, give the ground a thorough hoeing with a large hoe, to loosen the surface and destroy all weeds effectually; and in autumn cut down the decayed stalks of the liquorice, and nothing more is necessary to be done till spring; when, in February or March, give a slight digging between the rows; during spring and summer, keep down all weeds by broad-hoeing; and in autumn, when the stalks are in a decaying state, cut them down to the surface of the earth.

In three years after planting, the roots of the liquorice will be fit to take up: and the proper season for this is, any time from the beginning of November till February; for it should neither be taken up before the stalks are fully decayed, nor deferred till late in spring, otherwise the roots will be apt to shrivel and diminish in weight. In taking them up, the small side-roots are trimmed off, and the best divided into lengths for fresh sets, and the main roots are tied in bundles ready for sale. It is of advantage to sell them as soon as possible after they are taken up, before they lose much of their weight. They are sold to the druggists from about twenty to thirty or forty shillings per hundred weight; and an acre of ground has produced three thousand and upwards, which has been sold for more than sixty pounds: but the price is commonly in proportion to the goodness of the roots.

Uses. The common liquorice is cultivated in most countries of Europe for the sake of its root. That which is cultivated in Britain is preferable to such as comes from abroad; this last being generally mouldy, which this root is very apt to become, unless kept in a dry place. The powder of liquorice usually sold is often mingled with flour, and probably too often with substances not quite so wholesome: the best sort is of a brownish yellow colour (the fine pale yellow being generally sophisticated), and of a very rich sweet taste, much more agreeable than that of the fresh root. Liquorice is almost the only sweet that quenches thirst; whence it was called by the Greeks adipson. Galen takes notice, that it was employed in this intention in hypoporic cases, to prevent the necessity of drinking. Mr Fulke, in his Medicina Gymnastica, recommends this root as a very useful pectoral; and says it excellently softens acrimonious humours, at the same time that it proves gently detergent; and this account is warranted by experience. An extract is directed to be made from it in the shops; but this preparation is chiefly brought from abroad, though the foreign extract is not equal to such as is made with proper care among ourselves.