Bumblebee Blues Skullcap

Bumblebee Blues skullcap flowers in early summer, covering the gap between the spring ephemerals finishing and the midsummer perennials getting started. Scutellaria 'Bumblebee Blues' reaches 18 to 24 inches tall and 24 to 30 inches wide, is hardy in Zones 4 through 9, and flowers about equally in full sun or part shade, which is uncommon enough to be worth planning around. Growth is steady rather than quick, so expect two seasons before it fills its stated width.

The flowers are hooded and salvia-like, deep cobalt blue with white throats, carried in large clusters up the stem. That hood is sized for bumblebees, which can push into the throat where smaller bees cannot. Bloom runs for several weeks at a point in the season when many native perennials are still in bud.

Stems are deep purple, and the dark green leaves carry toothed, purple-tinged margins, so there is something to look at before and after the flowers. It forms a clump and stays where it is planted rather than running at the roots. The plant is a hybrid between Scutellaria ovata and Scutellaria serrata, two species native to the eastern United States.

Average garden soil is enough, and drainage matters more than fertility. Skullcap will not tolerate sitting wet through winter, so heavy clay is worth amending and a low spot is worth avoiding. Once established the plant takes dry soil, including the dry shade under mature trees where most perennials sulk. It belongs to the mint family, a group deer generally pass over.