Pycnanthemum tenuifolium

Slender mountainmint’s frilly white blooms are an elegant invitation to pollinators in July. The plant’s narrow foliage creates a pleasing, fine texture which contrasts with broader leaved plants and adds variety to the garden.

A flower of meadows and forest openings, slender mountainmint produces its most abundant blooms in full sunlight, but will tolerate partial shade. The plant is adaptable to a wide range of moisture conditions and has good drought tolerance. Its short stature – typically under 2’ – makes it exceptionally useful in the garden, where it can be utilized along borders or to create patches between taller plants. When planted with natives like purple coneflower, early goldenrod, and dense blazing star, it is part of a knockout midsummer show.

Slender mountainmint spreads readily via rhizomes and is very good at filling in bare areas and preventing weed growth. Although this plant is a good competitor, gardeners shouldn’t be wary of it taking over, and indeed, curtailing its spread is an easy matter. One need only press a shovel into the soil at the desired perimeter of the mint patch to sever the plant’s spreading underground stems, and then pull the above-ground stems that are growing beyond this perimeter. This technique is called root-pruning, and it is typically done just once a year, early in the growing season.

In terms of pollinator value, slender mountainmint is exceptional. Its blooms offer accessible nectar to both long and short-tongued pollinators, and it attracts a diversity of visitors ranging from sweat bees and hover flies to bumble bees and butterflies. Summer azures are small, light blue butterflies that have a special fondness for white flowers and they love to visit slender mountainmint. And gardeners needn’t worry about deer crashing the party – they find the plant to be highly distasteful and almost never browse it.

Photo © Doug McGrady,CC BY 2.0