8. Mountain Mints (Pycnanthemum virginianum and P. muticum) Both of these native mountain mints (and many other members of the mint family) are excellent choices for Beneficial Borders. Short-toothed mountain mint (P. muticum) has broad clusters of small white flowers surrounded by unique, showy white bracts; it makes beautiful dried flowers. Mountain mints grow 2 to 3 feet tall and are hardy from zones 4 to 7. Not yet widely available, these plants can be ordered from Sunnybrook Farms, 440-729- 7232.