The mountain laurel, Kalmia latifolia, was first recorded growing in America in 1624, but it was not named until 1750 when Pehr (Peter) Kalm, a Swedish explorer and botanist, sent a specimen to his friend and teacher Carl Linnaeus, “the father of modern taxonomy” who formalized binomial nomenclature, the modern system of naming organisms. Linnaeus gave it the name Kalmia in honor of his fellow-botanist and latifolia, describing the “wide-leaflet” characteristic of the plant.
Mountain laurel is in the heath or heather family Ericaeae, which includes rhododendrons, azaleas, blueberries and cranberries. Mountain laurel is native to North America, found on rocky ridges and mountainous forest areas as far south as Florida’s panhandle, as far north as southern Quebec, as far west as Indiana and Louisiana.
The mature size is 5 feet to 12 feet tall with a similar spread. It is a broadleaf evergreen with the leathery, ovate leaves being 3-4 inches in length. The one inch, white to pink to deep rose flower clusters bloom late May to early June and the flowers last two weeks or more. Sometimes mountain laurel are listed as “shade tolerant”, but they will become leggy and do not bloom in shade, they prefer at least a half day of full sun.
Ten arching stamen are embedded in depressions on the inside rim of the flower. When a bee or other pollinator lands on the flower, the weight of the insect releases the stamen which flings up the pollen like a catapult and lands on the pollinator. All parts of Kalmia latifolia are poisonous if ingested, deer are apparently immune to any ill effects.
The mountain laurel was designated as Connecticut’s state flower in 1907 and there are a number of mountain laurel sanctuaries across the state. Nipmuck State Forest in Union has a one mile long hike amidst the laurels, first planted by the Civilian Conservation Corps in 1935. The 27,000 acre Pachaug State Forest in Voluntown, has a half mile trail with mountain laurels and the Arboretum at Connecticut College has 750 acres of preserved open space in New London with gorgeous mountain laurels, rhododendrons and azaleas. In the northeastern part of the state, Haystack Mountain in Norfolk, has a road lined with mountain laurel.
Mountain laurel is also called calicobush or spoonwood. It was called “spoon”wood because Native Americans used to make spoons from the wood. (Obviously at that point it was not known that all parts are poisonous if ingested.) In the 1940s they also began to use the shrub to make pipes. During World War II it was difficult to get briarwood from the Mediterranean region so the world’s largest pipe manufacturer, Dr. Grabow Pipes, moved from Chicago to Sparta, North Carolina to look for mountain laurel roots as a replacement. The part of the shrub used for pipes is a burl or root ball, this area collects and stores water for the plant. Depending on the age of the plant, the burl can range from the size of a cantaloupe to a medium beach ball. The wood is usually heavier, harder and denser than normal wood of the laurel and it will not readily burn when tobacco is lit inside the bowl of the pipe. Since it was so difficult to harvest the manufacturer made pipes out of mountain laurel for only a few years.
Richard Jaynes, Connecticut plant breeder, has introduced dozens of new cultivars including highly colored blooms and dwarf varieties. A beautiful flower to add to any landscape and in so doing to celebrate Connecticut’s and Pennsylvania’s state flower.
UCONN Plant Database – Kalmia latifolia
Mountain Laurel with Dick Jaynes YouTube Videos