Nicotiana tristis, or dull-purple tobacco: leaves lanceolate, wavy, clasping the stem; corolla salver-shaped, its tube not twice the length of the calyx, and scarcely longer than the obtuse limb. Gathered also by Commerson at Monte Video.
Nicotiana rustica, common English tobacco: leaves petioled, ovate, quite entire; flowers obtuse. The stalks of this seldom rise more than three feet high. Leaves smooth, alternate, upon short foot-stalks. Flowers in small loose bunches on the top of the stalks, of an herbaceous yellow-colour, appearing in July, and succeeded by roundish capsules, ripening in the autumn. This is commonly called English tobacco, from its having been first introduced here, and being much more hardy than the other sorts, insomuch that it has become a weed in many places.
Nicotiana rugosa of Miller, rises with a strong stalk near four feet high; the leaves are shaped like those of the preceding, but are greatly furrowed on their surface, and near twice the size, of a darker green, and no longer on footstalks.
Nicotiana urens, or stinging tobacco: leaves cordate, crenate; racemes recurved; stem hispid, stinging. Fructification in racemes directed one way and revolute, with bell-shaped corollas, and cordate leaves like those of Nicotiana rustica; but crenate, and the whole tree prickly. Native of South America.
Nicotiana glutinosa, or clammy-leaved tobacco: leaves petioled, cordate quite entire; flowers in racemes, pointing one way, and ringent. Stalk round, near four feet high, sending out two or three branches from the lower parts. Leaves large, heart-shaped, and a little waved.
Nicotiana pusilla, or primrose-leaved tobacco: leaves of oblong oval, radical; flowers in racemes, acute. This has a pretty thick taper root that strikes deep in the ground; at the top of it come out six or seven leaves spreading on the ground, about the size of those of the common primrose, but a deeper green. This kind was discovered by Dr. Houstoun at Vera Cruz, and he sent the seed to England.
Tabacum Minimum (Gen. Em. 358.) appears to be another species, hitherto unsettled, with a branched leafy stem, a span high; leaves ovate on footstalks, opposite; and stalked acute, greenish-yellow flowers. The N. minima of Molina (Poir. in Lum. Diet. iv. 481.), is probably another species, or perhaps the same.
Culture.—Tobacco thrives best in a warm, kindly rich soil, that is not subject to be over-run with weeds. In Virginia, the soil in which it thrives best is warm, light, and inclining to be sandy; and, therefore, if the plant is to be cultivated in Britain, it ought to be planted in a soil as nearly of the same kind as possible. Other kinds of soil might probably be brought to suit it, by a surface of proper manure; but we must remember, whatever manure is made use of, must be thoroughly incorporated with the soil. The best situation for a tobacco plantation is the southern declivity of a hill, rather gradual than abrupt, or a spot that is sheltered from the north winds: but at the same time it is necessary that the plants enjoy a free air; for without this they will not prosper.
As tobacco is an annual plant, those who intend to cultivate it ought to be as careful as possible in the choice of the seeds; in which, however, with all their care, they may sometimes be deceived. The seed should be sown in the middle of April, or rather sooner in a forward season, in a bed prepared for this purpose, of such soil that has been already described, mixed with some warm rich manure. In a cold spring, hot beds are most eligible for that purpose; and gardeners imagine that they are always necessary: but Mr. Carver[22] tells us, that he is convinced, when the weather is not very severe, the tobacco seeds may be raised without-doors: and for this purpose gives us the following directions:
“Having sown the seed in the manner above directed, on the least apprehension of a frost after the plants appear, it will be necessary to spread mats over the beds, a little elevated from the ground by poles laid across, that they may not be crushed. These, however, must be removed in the morning, soon after the sun appears, that they may receive as much benefit as possible from its warmth and from the air. In this manner proceed till the leaves have attained about two inches in length and one in breadth, which they will do in about a month after they are sown, or near the middle of May, when the frosts are usually at an end. One invariable rule for their being able to bear removal is, when the fourth leaf is shrouded, and the fifth just appears. Then take the opportunity of the first rains or gentle showers to transplant them into such a soil and situation as before described; which must be done in the following manner:—The land must be ploughed or dug up with spades, and made as mellow and light as possible. When the plants are to be placed, raise with the hoe small hillocks at the distance of two feet or a little more from each other, taking care that no hard sods or lumps are in it; and then just indent the middle of each, without drilling holes, as for some other plants.