A bee lands on a mountain mint plant. Submitted photo
The Arboretum at Penn State calls mountain mint (Pycnanthemum spp.) a “buzz”-worthy must-have for a pollinator garden. Indeed, it is worthy of a spot in any garden, especially if you are a beekeeper. Mountain mint nectar makes delicious honey.
The genus Pycnanthemum is a member of the mint (Lamiaceae) family and species in the genus found in Western Pennsylvania, which includes Clustered mountain mint (P. muticum, also called blunt or short-toothed mountain mint); hoary mountain mint (P. incanum); and three species native to Butler County, narrowleaf mountain mint (P. tenuifolium), whorled mountain mint (P. verticillatum) and Virginia mountain mint (P. virginianum).
All attract bees, wasps and small butterflies and deserve a place in a native plant or pollinator garden. However, if you only have room for one, clustered mountain mint would be the best choice, because mountain mint was found to be the plant most attractive to pollinators in the Penn State Bees, Bugs and Bloom Pollinator Trials 2012-2014. It also has been designated the perennial of the year for 2025 by the Perennial Plant Association.
Collectively, mountain mints are easy to grow in full sun to part shade and are not very fussy about soils or moisture, as long as there is good drainage. They are reasonably drought-tolerant and are not easily susceptible to pests or diseases. Depending on the species, they grow 1 to 4 feet tall with an upright, branching habit.
When established, they form a dense clump that naturally inhibits weeds. Tiny flowers, varying in color from white to pink-white to lavender, bloom from mid- to late-summer on flat clusters at the tips of branches. Leave the seed heads through winter to provide food for foraging birds, like American goldfinches (Spinus tristis) and chickadees. Seed heads of clustered mountain mint also are excellent for dried floral arrangements.
Clustered mountain mint has a pair of silvery-green bracts surrounding the pink-white flower clusters that provide an interesting focal point in the garden.
Similarly, hoary mountain mint leaves are covered with tiny, downy hairs giving them a frosted appearance and frame its lavender flowers with purple spots.
Narrowleaf and Virginia mountain mints have thin, green leaves and white flowers.
Whorled mountain mint has small, green leaves covered with hairs, providing it with its other common name — hairy mountain mint. Its flowers are lavender. Mountain mint leaves are highly aromatic, emitting a minty aroma when touched or crushed. The oils that create the minty fragrance inhibit deer, rabbits, voles and groundhogs from feeding on the plants. It also makes mountain mint a good choice to be planted in a sensory garden.
Picked before blooming, the leaves of Virginia, clustered, and narrowleaf mountain mints can be used to make herbal teas.
A white hoary mountain mint. Submitted photo
Clustered mountain mint can be planted with gayfeather (Liatris spp.), black-eyed Susans (Rudbeckia hirta) or bee balms (Monarda spp.), and native grasses such as little bluestem (Schizachyrium scoparium) and switchgrass (Panicum virgatum). However, all mountain mint species are welcome additions to a native plant or pollinator garden.
As members of the mint family, they can be aggressive in the garden, spreading by shallow, branching rhizomes. Allow them to naturalize over a large area, use them for erosion control, or pull the rhizomes in spring to keep them manicured. Mountain mints may also be grown in containers.
To find mountain mints for your gardens, seek out local or online native plant nurseries. Increasingly, garden centers and nurseries are adding native plants to their inventories, and you can look for mountain mints there.
If you have questions about mountain mints or other native plants, telephone the Penn State Extension Master Gardeners of Butler County at the Garden Hotline at 724-287-4761, Ext. 7, or email the Master Gardeners at butlermg@psu.edu.
Mary Alice Koeneke is a Penn State Extension Butler County Master Gardener.
