Conditioning normally is done in moistening cellars or humidified rooms so the leaves can be han-dled without breakage. During conditioning further changes take place in the leaves. The preparation for sale usually consists of grading the tobacco and putting it in bales or packages of convenient size and weight for inspection. Grading varies from country to country, and it also depends on the use to which the leaves will be put. Most United States, Canadian, Central African, and Australian tobacco is sold by farmers at auction warehouses.
Buyers visiting farmers or local villages purchase other crops by private arrangement.
Much of the world's tobacco is sold on a noncompetitive basis in countries where a government monopoly is the only buyer. After purchase, tobacco may be regraded. Then, for most tobacco, the exact amount of moisture needed for aging is added and the leaves are packed in cases or in hogsheads, which are casks or barrels. The tobacco ages for two to three years, undergoing chemical and physical changes, before it is ready for use. The most common uses of tobacco are for cigarettes, cigars, pipe tobacco, chewing tobacco, and snuff.