Kalmia is a plant genus comprising about 8 species of shrubs that are native to eastern regions of North America. One species that is particularly popular among gardeners and landscapers is Kalmia latifolia. This evergreen shrub is commonly known as the mountain laurel. It grows 7 to 15 feet in height and spreads 3 to 5 feet. The leathery, oval leaves surround pink flowers that bloom in bunches at the start of summer. When considered with its symmetrical form, this shrub can be planted as an ornamental in most locations.
There are several things to consider when planting and growing the mountain laurel. The condition of the soil, the climate, and certain pests or diseases can affect the health of Kalmia latifolia.
Climate
This shrub thrives in hardiness zones 4 to 9. Its natural habitat consists of cool meadows and slopes. It prefers partial shade, instead of full sunlight.
Soil Conditions
Plant the mountain laurel in rocky or sandy soil that is well-draining. Poorly draining soil may lead to root rot, which is a condition that deteriorates the structure and function of the plants root system. This shrub prefers acidic soil. It is a good idea to add mulch to protect it from the elements.
Watering and Fertilizers
Keep the soil relatively moist by watering it occasionally. This shrub is drought tolerant, so avoid over-watering this plant. Too much water can hinder its growth.
Propagation
The best way to propagate this plant is by sowing seeds. Collect seeds late in the season or purchase at a nursery. It is recommended to use cold-moist stratification to promote germination.
Pests and Diseases
This shrub doesn’t have a significant insect problem, but butterflies use it as a larva host. Birds are also attracted to it.
Reference:
Kalmia latifolia – Lady Bird Johnson Wildflower Center
Kalmia latifolia – North Carolina Cooperative Extension