Would you like to enjoy the beautiful flowers of mountain laurel plants (Kalmia latifolia) on your own property? These bushes are not difficult to grow if you follow a few simple rules. Learn about some of the best cultivars and also how these shrubs differ from their more famous namesakes.
Botany, Plant Traits, Growing Conditions
Mountain laurel plants can be grown in USDA plant hardiness zones 5 to 9 and will typically reach 5 to 8 feet in height (by a similar width) in the wild, although it is possible for them to become even larger. Cultivars generally stay shorter and even include dwarfs. While they are classified as shrubs that grow in shade and will tolerate deep shade, you will get more flowers if you plant them where they will receive a bit of sun, so select a location in light shade or dappled shade for optimal flowering.
Broadleaf evergreens, mountain laurels are a multi-stemmed shrubs that bear glossy, deep-green leaves that are attractive in all seasons. On older bushes, the branches can become quite gnarled, which lends them character. But it is the shrubs' spring or summer flower display that makes them a special part of the woodlands to which they are native in the eastern part of North America.
The flowers, which appear in clusters, offer landscape value not only with their color, but also with their unusual shape (particularly the buds). Bloom time is around the end of May or the beginning of June in zone 5. The 1-inch wide individual flowers come in the form of five-sided cups. These flowers are speckled and range in color, in the wild, from white (useful in moon gardens) to pink.
Mountain Laurel Cultivars
The cultivars now available offer other color options (many are bicolored). Many are 4 to 6 feet tall, but there are also several dwarfs (3 feet in height or less). The European Kalmia Society provides a full list of cultivars. Here are some of your best choices:
- Bay State: pink flowers with coral or salmon color mixed in
- Black Label: flowers bear white center and margin, with an almost black band sandwiched in between
- Bridesmaid: bicolored flowers (dark-pink margin with a white center)
- Elf: white flowers; 3 feet x 3 feet
- Firecracker: buds a deep-red, opening to become light-pink flowers; a bit narrower in shape than many cultivars, maturing to 3 feet tall x 2 feet wide
- Fresca: flowers sport a chocolate-purple band on white petals
- Galaxy: burgundy and white colors on star-shaped flowers that are formed quite differently from those on wild mountain laurels
- Madeline: remarkable not for its floral coloration, which is white, tipped with pink, and speckled with burgundy, but for the fact that it is double-flowered
- Minuet: white center speckled with cherry-red markings and surrounded by a cherry-red margin; reaches a mature size of just 3 feet by 3 feet
- Peppermint: red lines radiating from the flower center out to the edges of the petals, reminding people of the hard candy by the same name
- Silver Dollar: another type whose flower is remarkable not for its colors (white, with sparse pink markings), but for something else; in this case, its relatively large size of 1 1/2 inches across)
- Tightwad Too: what is noteworthy with this kind is that its pink buds never open, which is a nice feature for those who actually prefer the look of mountain laurel in bud, rather than in full bloom
- Tiddlywinks: medium-pink flowers; another dwarf, at 3 feet x 3 feet
How to Grow Mountain Laurel Bushes
Although many people try to propagate them by transplanting mountain laurels from the wild, you are far more likely to have success if you purchase these shrubs from a nursery. Digging up wild plants usually causes sufficient root damage to thwart your efforts at saving a buck. Your chances of success will increase significantly if you buy a balled and burlaped plant from a nursery.
Soil is another factor to keep in mind in growing mountain laurels. Your soil should be moist but well-drained. This combination is not always easy to achieve. But adding peat moss, compost, and sand before planting is a step in the right direction.
The soil pH of the ground should be on the acidic side. What should you do if your ground is too alkaline? When growing acid-loving plants like mountain laurel, rhododendron, and azalea, it can be helpful to fertilize with a fertilizer such as Holly-Tone, which will acidify the soil over time.
Mulching will help retain some of that moisture the plants need. The mulch will also keep the soil cool, which mountain laurels like. Pine needles and wood chips can both make for excellent mulches. Whichever kind of mulch you use, apply a 2 to 6 inch layer.
When planting mountain laurels, do not plant too deeply. Make sure the shrub's "crown" (where its trunk meets its roots) is not buried. Buried crowns will suffer from rot, and your shrub will die.
Mountain laurel plants rarely need to be pruned, although pinching off the seed heads after blooming time is over seems to promote better flowering for the next season. If you do choose to prune (to make the shrubs bushier, for example), do so just after the flowering season has ended. Should your mountain laurel plants get too tall and/or gangly for your landscape design, cut them back almost to ground level to rejuvenate them. These tough shrubs can take a severe pruning when necessary. From stubs just a few inches above the ground, new foliage will arise, and your plants will mature into large shrubs once again in about ten years’ time.
As evergreens with pretty flowers, mountain laurels boast a number of potential uses in the landscape, including in foundation plantings. If you garden in eastern North America, you may wish to play up their indigenous status by using them in woodland gardens.
Relation to Greek Mythology, Julius Caesar, and the Olympics?
Mountain laurel shrubs are a close relative of rhododendrons and azaleas, all three shrubs belonging to the heath family. They are not related to their namesakes, though, the bay laurel trees (Laurus nobilis), with which they are sometimes confused.
Bay laurels enjoy much better name recognition. These small, Mediterranean trees are prominent in history and literature. The ancient Greeks and Romans fashioned bay laurel tree’s leaves into wreaths, to be worn as crowns by the victors in sporting events and military campaigns. When you think of Julius Caesar, you probably picture him wearing just such a wreath.
Ever since, the foliage of bay laurel trees has been a symbol of victory. It is still used as such for the Olympics. We even have the expression, “to rest on your laurels,” meaning to be overly content with your past achievements. It is also this more famous laurel that is used as a flavoring agent in cooking, often referred to as “bay leaf.”
In Greek mythology, the nymph, Daphne was transformed into a bay laurel tree (not a daphne shrub, oddly enough), to save her from Apollo’s unwelcome advances. Apollo was chasing this daughter of the river-god, Peneus through the woods when the magical metamorphosis occurred. The tale of her transformation has been passed down to us by the Latin poet, Ovid, in the appropriately titled Metamorphoses. Edith Hamilton, in her Mythology, relates the tale to us in English with her usual charm:
“She felt his breath upon her neck, but there in front of her the trees opened and she saw her father’s river. She screamed to him, ‘Help me! Father, help me!’ At the words a dragging numbness came upon her, her feet seemed rooted in the earth she had been so swiftly speeding over. Bark was enclosing her; leaves were sprouting forth. She had been changed into a tree, a laurel.”
But mountain laurel is related to its namesake, the bay laurel tree, only in name. The common name for Kalmia latifolia derives from the fact that, when Europeans encountered it in the New World, it reminded them superficially of Laurus nobilis. But while the foliage of the latter is used as a culinary herb, mountain laurel is a poisonous plant, as you might suspect from its association with the aptly named "lambkill" (Kalmia angustifolia) shrub. It is another reminder of why we use scientific names when discussing plants: Confusion over plant names can have dire consequences.