LANSING, New York–If you’ve grown mountain mint (Pycnanthemum sp.), you must love it as much as I do. If you don’t know it, let me tell you about it. It’s a native of the eastern United States and is, it seems to me, pretty exotic for being a plain American. Its scent, fresh and exhilaratingly minty, seems to restore my spirits as I inhale it. I don’t have to rub the leaves to release the aroma: it wafts my way when I’m weeding anywhere in the vicinity.
My plant stands 2 1/2 to 3 feet tall on rigid stems that are clothed in opposite pairs of rounded, lance-shaped leaves, smooth and pointed. It’s a nice mound of solid green until late summer, when I suddenly note a sort of glow in that area of the garden and see that each stem is topped with clusters of small pinkish flower heads: flat pincushions covered with tiny, two-lipped flowers and embraced by two small, painted opposite leaves.
What is so dramatic about this metamorphosis is that all the flower clusters and all the leaves on the upper part of the plant appear to be covered with hoarfrost, a fine, luminous silver bloom such as is found in autumn on certain plums and grapes. It makes a mass of green and silver that lights up the garden.
Pycnanthemum is enterprising, sending its stolons into the territory of its neighbors, but it’s so much more restrained than ordinary mints that it is not a garden menace, at least not in our cold climate. Elsewhere, you might need to plant it in clay pots and sink them in the ground, which is what I do with my pretty gray plants of Mentha longifoliasubsp. himalayensis and M. buddleioides. Each spring, I dig them up, divide, repot, and replant them, firmly entrapped in their containers. Some plants must be dealt with severely.
In my bay window are pots of garden plants that I overwinter in the house: rosemary, sweet marjoram, and bay, along with rooted cuttings of ornamentals such as the lacy white Senecio leucostachys, the dark purple sweet potato vine Ipomoea batatas ‘Blackie’, Salvia ‘Indigo Spires’, and rose-leaf sage (S. involucrata). Luckily, my fall cuttings all root cheerfully and swiftly in jars of water. Together with geraniums and jasmine, these plants crowd the window, each elbowing the other in an effort to get the winter sunlight. It’s such a relief when I can finally carry them all outdoors–it’s like releasing a bunch of frantic, pent-up schoolchildren.
S. involucrata is a lovely Mexican plant that’s worth the time to root, pot up, and overwinter indoors. It grows to a bushy 2 1/2 to 3 feet tall, its red stems decorated with opposite pairs of long, very pointed, creamy green leaves with red undertones. In July or August, curious terminal rosy flowers appear. They consist of a pink, central knob surrounded by upward-facing rose-colored tubes that flare into small, hairy petals–a droll sort of flower. I take about a dozen cuttings every fall to ensure that I’ll have several groups of plants to bloom near and with the late roses and Japanese anemones. They are a symphony in pink.