Bee balm ‘Purple Rooster’

* Common name: Bee balm ‘Purple Rooster’

* Botanical name: Monarda didyma ‘Purple Rooster’

* What it is: ‘Purple Rooster’ is a summer-blooming U.S. native perennial that’s different in two ways from most bee balms – 1.) its flowers are violet-purple instead of traditional red, and 2.) it’s highly resistant to the powdery mildew leaf disease that plagues most bee balms.

This variety was one of the top-scoring bee balms in Mt. Cuba Center’s 2014-2016 trials, where evaluators said it showed no signs of mildew at all.

Like most bee balms, ‘Purple Rooster’ is very attractive to bees, hummingbirds, and butterflies but not a target of deer and rabbits.

* Size: Including the flower spikes, plants grow about three feet tall. ‘Purple Rooster’ is more clumping and less spreading than many other bee balms, but it can reach about three feet across after three or four years in the ground.

* Where to use: Bee balms do best in full sun. Sites with good air circulation also help head off mildew issues.

Since bee balms also appreciate damp soil (although not to the point of sogginess, especially in winter), ‘Purple Rooster’ is a good choice in a rain garden or any moist, well drained, sunny site.

Good locations include meadows, pollinator gardens, and perennial border plantings.

* Care: Water in dry spells. Fertilizer is usually not needed.

Flower spikes can be cut off after bloom, and foliage clumps can be cut back to the ground after a killing frost in fall or at the end of winter.

Clumps can be dug, divided, and replanted in early spring if plants are spreading beyond where you want.

* Great partners: ‘Purple Rooster’s’ flower color pairs well with other summer-blooming pastel perennials, such as purple coneflowers, catmint, ornamental onions, betony, and liatris. Little bluestem and blue-tinted varieties of switchgrass are good textural partners.