Onions.—Two kinds of onions are cultivated throughout the country: Allium cepa, the large onion which is seen to perfection in the Kano markets, and Allium ascalonicum which is usually termed the shallot, and is cultivated to a larger extent in the localities where manure is scarce.
The variety of large onion grown in Kano is pink upon the outside, and for this reason, according to inquiries conducted by the Imperial Institute, is said to be quite unsuitable for the English market; the white Egyptian onion being preferred.
Cultivation.—The cultivation of onions is, perhaps, more carefully carried out than that of any other crop, and may be described from that seen at Lemu in Nupe. The seed is sown closely in beds of soil which have previously been enriched with manure, and the surface is covered with straw until the young plants are a few inches in height. Transplanting into new beds, which are strewn with cow and goat manure, is the next operation, the plants being put in at about 4-6 inches apart. The whole cultivation is done during the dry season, and the beds are irrigated by means of channels supplied with water raised from streams or wells, in the north by shadufs, or in the Nupe country by people conveying the water in calabashes.
The market price varies greatly in different districts, and is immediately influenced by any reduced supply. There is said to be a very good demand for the large onions in the Southern Nigerian markets, and there should be no difficulty in getting them to Lagos, as they have been brought from Kano to London in good condition.
Minor Crops.—Okra (Hibiscus esculentus), “Kubiewa,” a species of Solanum resembling a small tomato called “Yalo,” the sorrel Hibiscus (H. Sabdariffa) called “Yakwa,” a pumpkin called “Kubiwa,” and the aubergine (Solanum melongena), are grown upon a small scale, and chiefly in the vicinity of houses.
OTHER FIELD CROPS. Dye Plants.—Indigo is the chief dye used in the country, and is prepared in the northern provinces from a species of Indigofera, which has not been accurately determined.
In Ilorin and Kabba the plant used is Lonchocarpus cyanescens, and the wild trees of this species may be seen preserved in the cultivated fields.
Camwood, a name applied to the red wood obtained from several species of Pterocarpus and from Baphia nitida, in different parts of West Africa, is obtained chiefly from P. erinaceus in Northern Nigeria, and is used by the natives for staining the skin. It is preserved in the fields cleared for grain cultivation.
Henna is obtained from Lawsonia inermis, which is regularly planted as a sole crop in the northern provinces and Kontagora. The use of it is generally to replace camwood as a red dye where that tree is scarce.
Tobacco.—The cultivation of tobacco (Nicotiana tabacum) is carried on in almost every part of the country, but for native use is generally made into snuff or into ropes, plaits, and targets, for sale in those places where it is smoked. (Cf. Bull. Imp. Inst., vol. xv. [1917], p. 32.)