Pycnanthemum sp.(Mountain Mints)
Mountain mint

Zone: 4 to 8

Soil: sand to loam

Light: Full sun to part sun

Bloom colour: White

Bloom period: July to August

Height: 2 to 3 feet

Moisture: Dry to medium

Attracts: A variety of bees and wasps.

Notes: If I were forced to plant just one species to attract bees and butterflies, it would be a mountain mint. These plants attract a huge diversity of bees and beneficial wasps and they are a dream plant for entomologists. They have a long blooming period and they are easy to grow. Pycnanthemum virginianum, the most common species, grows well in a variety of conditions and is quite drought tolerant. P. tenuifolium is more drought tolerant while P. pilosum is more tolerant of clay soils. All three of these plants, which look very similar to each other, are native to Ontario and a large part of the North East. All of them naturally occur in prairies and savannahs.

Another species worth mentioning is Pycnanthemum muticum, which has various common names. In addition to the flowers, it has large silvery bracts which add a lot of ornamental value for gardeners. It requires good drainage, but it is not drought tolerant. It will grow well in part-sun. It is native to the Eastern half of the USA.

These plants tend to spread out a bit, but they are not that large and it is worth planting a few together. They are easy to keep in check by pulling or by using root barriers.

In addition to the three species already mentioned, Pycnanthemum incanum is also native to Ontario and has a provincially endangered status.

Pycnanthemum viginianum

Bicyrtes on pycnanthemum

Pycnanthemum viginianum with a sand wasp

Xylocopa virginica

Pycnanthemum viginianum with a carpenter bee
Mountain mint with thick headed fly
Pycnanthemum tenuifolium with a conopid fly
Mountain mint with Virginia Ctenucha

Pycnanthemum muticum

Pycnanthemum viginianum with Virginia Ctenucha Moth (see comparison with yellow collared scape moth) Pycnanthemum muticum with its silvery bracts.
Pycnanthemum tenuifolium
Narrow leaf mountainmint covered in pollinators