Tobacco leaves need to be cured and aged after harvesting before they can be used in cigars, pipes, cigarettes and chew. The curing process is used to dry fresh leaves of tobacco and prepare them for ageing; in most cases, the flavour of freshly cured tobacco is not desirable. Most home growers use the air-curing method, as it is extremely effective and does not require a curing facility.
Harvest your tobacco when the upper leaves have a yellow tinge. Remove leaves from the stalk singly, or by cut off the stalk at ground level with a knife or harvesting tool. Tobacco harvested by the stalk should be left to stand in the field until it wilts before curing, according to the University of Kentucky's Department of Agronomy.
Bunch single leaves of tobacco loosely and hang them or place them in your desired curing facility. Leaves still attached to the stalk can be hung by the stalk or left whole until after curing is finished.
Hang the tobacco leaves in a well-ventilated, dark room. The leaves should not be exposed to any sunlight or other weather, especially wind.
Keep humidity between 65 and 70 per cent. Anything below this can cause the tobacco to cure too slowly, reducing the weight of the tobacco leaves. Tobacco cured in high humidity is prone to rotting, which can ruin the crop. Use a humidifier or dehumidifier as necessary.
Maintain a temperature of 15.6 to 32.2 degrees Celsius throughout a 24-hour period. Depending on when you cure the tobacco, you may need to use a temperature-controlled environment to do this. In most cases, it is easiest to cure tobacco based on your local weather; in most locations, the latter part of spring will stay in these temperature ranges.
Monitor temperatures closely. If the temperature drops below 15.6 degrees Cor a few hours one night, nothing needs to be done. Temperatures over 90 should be avoided to prevent the tobacco from curing too quickly. If curing in a barn or other outside facility, installing a thermometer inside the area where the tobacco will be cured is a good idea; the area will likely be 10 degrees warmer or cooler than the outside temperature.
Wait six to eight weeks for the tobacco to completely cure. The air-curing process results in high nicotine content as well as a slightly sweet, soft tobacco flavour.
Sun-cure tobacco leaves by leaving the harvest plants outside in direct sunlight. This method is popular for tobacco used in cigarettes, especially those sold in Mediterranean countries, according to online tobacconist, The Tobacco Seed Company.
Fire-cure tobacco by maintaining a small, low-burning fire in a building where harvested tobacco leaves are suspended. This process can take up to 10 weeks in order for the leaves to completely cure, yet it gives the tobacco a smoky taste and smell. Nearly all tobacco used in pipes or for chew is fire-cured.
Flue-cure tobacco for cigarette tobacco that is sweet and high in nicotine. With this method, leaves are kept in a highly heated room, although they are not exposed to any fire or smoke. The method only takes about a week, and is the standard for tobacco products made in Virginia.
Tobacco needs to age at least a year after curing before it can be used.
When using any heat-curing methods, make sure the facility you are using is meant to do so and that it is monitored closely.