Mint production and pest management in Indiana
The mints are grown for the essential oils that they produce in specialized glands on the leaves and stems. This oil is readily recovered by steam distillation of the harvested hay. Peppermint and spearmint oils are widely used to flavor chewing gum, candy, pharmaceuticals, toothpaste and other oral hygiene products. More than 30% of the mint oil produced in the U.S. is exported to Europe and other countries around the world.
There are two types of mint grown for their essential oils. These are peppermint (Mentha piperita) and two species of spearmint: native or American spearmint (Mentha spicata), and Scotch spearmint (Mentha cardiaca). All of these originally came from selections from native plants, and until the 1970s there were no commercially developed varieties of any of these species.
Presently, there are four varieties of peppermint: Black Mitcham (the original selection from the wild), Todds Mitcham, Murray Mitcham, and Roberts Mitcham. The last three varieties were developed to reduce losses from the highly destructive disease Verticillium wilt. Native and Scotch spearmints are very similar.
Native spearmint is used most often to flavor toothpaste and dental hygiene products. Scotch spearmint has a milder, more pleasant taste and is used in chewing gum and confections. At present, no new varieties of either type of spearmint are widely grown. Breeding and selection work continue in the development of new varieties.