Reproduction
Peppermint is a hybrid between Mentha
aquatica (water mint) and Mentha spicata
(spearmint). A hybrid is a crossing of two different species to
make a new species. It is common to create a new species that is
sterile, meaning it is not able to reproduce. This is the case
for Mentha x piperita. Peppermint plants to do
produce fertile seeds and reproducing only by vegetatively
spreading its rhizomes. Rhizomes are simply a horizontal plant
stem that grows underground; roots are typically grown off of
the rhizomes.
Like other true mints, propagation is recommended by division, cuttings, or ground layering. When someone is propagating a plant, they are in a sense aiding the plant in reproduction, because they (the plant) are unable to. Check out Habitat & Adaptation to see how peppermint plants survive in the environment without being able to reproduce.
There are two strains or variations of Mentha x piperita. The first variation is known as Mentha x piperita var. piperita. This is also called black peppermint. Black peppermint plants can be distinguish by their purplish stems. This type of peppermint is also a good choice for candies and beverages. White peppermint or Mentha x piperita var. officinalis is the second variation of peppermint. These peppermint plants have paler green leaves, more slender stems, and a milder fragrance and taste.