Sheepkill Kalmia latifolia

Mountain laurel is a broadleaf, evergreen shrub or small tree in the blueberry family (Ericaceae) native to eastern North America, where it is found in a variety of habitats, including open rocky or sandy woods, meadows, balds, mountain slopes, acidic forests and woodland margins. Linnaeus named the genus after Swedish botanist Peter Kalm (1716–1779), who botanized in eastern North America from 1747 to 1751. The species epithet is Latin for “broad leaf.”

Mountain laurel tolerates a wide range of light conditions, from full sun to full shade, but grows best in partial shade (morning sun with early to mid-afternoon shade) and in cool, moist, acidic, humus-rich, well-drained soils. Mulch to retain moisture and keep root zones cool. The plant does not grow well in heavy clay soils or wet soils. In heavy soils, raised plantings should be considered to promote better drainage. Remove spent flower clusters immediately after bloom and prune branches back lightly after bloom to promote bushy growth. When pruning, keep in mind that next year's blossoms will appear on old growth.

It can grow slowly to 6 to 10 feet tall as a dense, rounded shrub, opening up and developing gnarly branches with age. It will rarely grow to 32 feet tall as a small tree, particularly on slopes in the Appalachian Mountains. It blooms in late spring to early summer, and its buds and fruits are showy. Attractive foliage makes this a good choice for year-round interest. Flowers have touch-sensitive anthers contained in pockets in the corolla. When triggered by a bee, the filaments spring out of their pockets in the corolla and dust the bee with pollen. There are many cultivars available, including some that are heat-tolerant and even some that are dwarf varieties. 

Plant mountain laurel in a meadow, naturalized or woodland area, and use it as an accent or flowering shrub in a native, children’s, butterfly or pollinator garden.

Fire Risk: This plant has a high flammability rating and should not be planted within the defensible space of your home. Select plants with a low flammability rating for the sites nearest your home. 

Quick ID Hints:

• Evergreen shrub with sympodial growth and elliptic leaves
• Fruit, buds, or inflorescence are visible year-round
• Terminal clusters of bell-shaped flowers are present in the late spring
• Flowers have inner purple markings and 10 anther pockets
• Old trunks and limbs are gnarly, cracked, and crooked

Insects, Diseases, and Other Plant Problems: Mountain laurel is susceptible to borers, scale, white fly, and lace bugs. It is also susceptible to leaf spots and blights. While the nectar poses no problems for bees, if honey bees feed heavily on these plants, they are known to produce honey that may be toxic for humans.