The flowers are hexagonal, sometimes appearing to be pentagonal, ranging from light pink to white, and occur in clusters.

[10] Physicist Lyman J. Briggs became fascinated with this phenomenon in the 1950s after his retirement from the National Bureau of Standards and conducted a series of experiments in order to explain it.

[12][13] The plant was first recorded in America in 1624, but it was named after the Finnish explorer and botanist Pehr Kalm (1716–1779), who sent samples to Linnaeus.

Many of the cultivars have originated from the Connecticut Experiment Station in Hamden and from the plant breeding of Dr. Richard Jaynes.

Jaynes has numerous named varieties that he has created and is considered the world's authority on Kalmia latifolia.

[15][16] In the UK the following cultivars have gained the Royal Horticultural Society's Award of Garden Merit: The wood of the mountain laurel is heavy and strong but brittle, with a close, straight grain.

[21] It has never been a viable commercial crop as it does not grow large enough,[22] yet it is suitable for wreaths, furniture, bowls and other household items.

Mountain laurel is poisonous to several animals, including horses,[24] goats, cattle, deer,[25] monkeys, and humans,[26] due to grayanotoxin[27] and arbutin.

[26] Symptoms include irregular or difficulty breathing, anorexia, repeated swallowing, profuse salivation, watering of the eyes and nose, cardiac distress, incoordination, depression, vomiting, frequent defecation, weakness, convulsions,[28] paralysis,[28] coma, and eventually death.

[26] The Cherokee use the plant as an analgesic, placing an infusion of leaves on scratches made over location of the pain.