Mint plants (Mentha spp.) include traditional herbal mints, varieties with floral or chocolate fragrances and soft- or woolly-leaved types. These rapidly growing, perennial plants are often vigorous spreaders that become invasive over time. Features shared by most varieties are fragrant foliage, bell-shaped or tubular flowers, square stems and underground runners. You can help prevent mint from taking over your garden by growing it in containers, or another option is to grow mint in semi-wild areas of your yard, where it will be an effective ground cover but have its spread controlled.
Peppermint (Mentha x piperita) and spearmint (Mentha spicata) are mints for the herb garden. Hardy in U.S. Department of Agriculture plant hardiness zones 5 through 9, peppermint is usually grown for its aromatic, dark-green, toothed leaves, which exude a fresh, sharp scent when crushed. Growing 1 to 2 feet tall and wide, peppermint features small, pink to lavender flowers on short spikes in summer. One of peppermint's parents is spearmint, the leaves of which have a slightly sweeter fragrance and taste. Spearmint grows up to 2 feet tall and 3 feet 3 inches wide, and it is hardy in USDA zones 3 through 7. Flowering in late summer, spearmint bears small, pale-pink flowers.
Brushing past mints in garden borders releases a burst of fragrance. Varieties suitable for those locations include "Lavender" mint (Mentha x piperita "Lavender"), which carries a rich, flowery scent in its gray-green leaves. In summer, its showy, butterfly-attracting, lilac flowers appear. "Lavender" mint grows 2 to 3 feet tall and wide. Another option for garden borders is "Chocolate" mint (Mentha x piperita f. citrata "Chocolate"). It grows 1 to 2 feet tall and wide, and its chocolate-scented leaves are dark green. Bearing small, lavender flowers in summer, "Chocolate" mint has few insect or disease problems. Both "Lavender" and "Chocolate" mint are hardy in USDA zones 5 through 9.
Paths and Ornamental Beds
Ornamental mint varieties are planted for their forms and foliage. Among that kind are Corsican mint (Mentha requienii) and horsemint (Mentha longifolia, Mentha incana or Mentha sylvestris). Corsican mint grows in dense mats of tiny leaves and threadlike stems, forming patches 1/2 to 1 inch tall and 12 inches wide or wider. Tolerating light foot traffic, Corsican mint gives off a fresh fragrance when crushed. Horsemint features woolly, gray foliage and lavender-blue summer flowers, and it grows 1 1/2 to 4 feet tall and 3 to 6 feet wide. Corsican mint and horsemint are hardy in USDA zones 6 through 9.
Slowly spreading mints are useful to grow where space -- or when time for controlling the plants -- is in short supply. Such varieties include "Bowles Mint," also called Bowles apple mint (Mentha rotundifolia "Bowles Mint"). It is less invasive than some other mint varieties and offers soft, rounded, light-green leaves with an apple-mint fragrance. Growing 2 feet tall and wide, "Bowles Mint" is hardy in USDA zones 6 through 10. Perennial in USDA zones 5 through 8, Margarita mint (Mentha margarita) spreads by overground runners, which makes its growth simple to control. Margarita mint features tiny, lime-scented, bright-green leaves and very small, lilac or purple flowers during summer. Clumps of the plant grow 6 to 12 inches tall and 18 to 24 inches wide.