The 2025 Perennial Plant of the Year: Clustered Mountain Mint
A pollinator’s delight
Each year, the Perennial Plant Association, a membership group of plant and garden professionals, votes one species or cultivar Perennial Plant of the Year (view them all here). Criteria for the award include a wide growing range and availability, resistance to pests and diseases, ease of care and, of course, beauty, preferably in more than one season. Named Perennial Plant of the Year for 2025 is clustered mountain mint (Pycnanthemum muticum).
Beloved by bees and butterflies, clustered mountain mint blooms from midsummer into autumn, with eye-catching silver bracts surrounding bunches of tiny tubular flowers in a very light pink. These unique flowers sit atop upright stems that reach two to three feet tall. Deer- and rabbit-resistant, mint-scented leaves line the stems, which rise from rhizomes that spread through the soil to create a dense ground cover.
Common name: Clustered mountain mint, short-toothed mountain mint
Botanical name: Pycnanthemum muticum
Exposure: Full sun to part shade
Flowers: Bunches of small, light pink, tubular flowers appear from midsummer to fall. Silvery bracts (modified leaves) surround the flower clusters.
Foliage: Medium green, oval-shaped leaves with a minty scent said to deter deer and rabbits.
Size and habit: Clustered mountain mint grows two to three feet tall and at least as wide. New stems arise from rhizomes that spread through the soil. Because of its growth habit, clustered mountain mint works well as a ground cover; it will fill space as its rhizomes extend, creating a dense stand of stems to shade out weeds.
Origin: Pycnanthemum muticum grows naturally in roughly the eastern half of the United States, inhabiting open meadows and low woodlands. Clustered mountain mint is one of several North American native species honored by the Perennial Plant Association in recent years, including butterfly weed (2017), 'Jeana' tall phlox (2024) and little bluestem (2022).
How to grow it: This perennial grows in full sun to part shade and moderately moist to damp soil, although it needs good drainage. It will grow in clay soil. More sun results in heavier flowering. Lean soil and drier conditions reduce its tendency to spread. In moist soil it can be aggressive, but the rhizomes are easy to chop back to fit an allotted space.
Clustered mountain mint is best thought of as a supporting-role plant in perennial combinations. Good companions for clustered mountain mint include deep-rooted prairie grasses and summer-flowering, moisture-loving perennials that won’t be outcompeted, such as black-eyed Susans (Rudbeckia), beebalms (Monarda), Joe Pye weeds (Eutrochium) and, for spring bloom, bluestars (Amsonia). USDA Zones 4–8.
Image credits, top to bottom: Fritz Flohr Reynolds/CC BY-SA 2.0/Flickr.com; cultivar413/CC BY 2.0/Flickr.com
