By Harold McGee
The mint family is a large one, with around 180 genera, and it provides more of our familiar kitchen herbs than any other family. Why such generosity? A fortunate combination of several factors. Members of the mint family dominate the dry, rocky Mediterranean scrublands where few other plants grow, and they cope with their exposed situation with a vigorous chemical defense. Their chemical defenses are located mainly in small glands that project from their leaves, external and therefore expandable storage tanks that can make up as much as 10% of the leaf’s weight. And members of the mint family are both promiscuous chemists and promiscuous breeders: individual species make a broad range of aromatic chemicals, and they readily hybridize with each other. The result is a great variety of plants and aromas.