The mountain laurel (Kalmia latifolia) is a medium-sized evergreen bush also known as calico bush or ivybush. It is a beautiful native American shrub with glossy leaves and small, star-shaped white and pink flowers. The flowers grow in attractive, eye-catching clusters in mid to late spring.
Mountain laurel is hardy in U.S. Department of Agriculture Hardiness zones 5 through 9. It’s average size is 8 feet tall and wide. It is a lovely bush for the outskirts of a woodland garden or as a foundation plant. It is beautiful enough to have earned the State Flower title for the state of Connecticut. Consider using the mountain laurel in place of the later blooming rhododendron. The shape, appearance, and needs of the two shrubs are very similar.
How to Grow and Care for Mountain Laurel
Mountain laurel is easy to grow from transplants. While many plants that you might run across in the wild will not transplant well, young mountain laurels are highly adaptable. Most of us will probably not find one in the wild though, so we’ll have to hunt for our mountain laurel at our local nurseries. Mountain laurel tends to sell out early in the season, so plan ahead and beat the crowd. Select a variety that will work well in your region.
Mountain laurel is a sun-loving plant. It will especially appreciate several hours of morning sun and a partially sunny afternoon. If you can plant your shrub where this preference can be met, you will be rewarded with bountiful blossoms.
Once you have selected a sunny site to plant your mountain laurel in, treat it to acidic, well-drained soil. To add acid to your soil before planting, mix peat moss into your soil. Every spring before your mountain laurel blooms, add an acidic fertilizer into the soil in the form of peat moss, compost, or acidic mulches, like shredded bark or pine needles. The mulch will serve dual purposes: it will nourish your plant with the acid it loves and it will maintain soil moisture.
Mountain laurel needs to be watered regularly. The soil can feel moist to the touch at all times, but it will be happy if left a bit dry, too. It would rather be dry than waterlogged.
While pruning isn’t a must do, you can prune your mountain laurel to maintain its shape and to encourage flowering for the next season. Timing is everything when pruning this bush, so prune as the flower buds begin to fade away. If the buds are starting to drop themselves, it is too late to prune. You don’t want to make the mistake of pruning off the growth buds for next year.
Pests and Problems
Mountain laurel is susceptible to the lacebug. This nasty little pest sucks the moisture out of the leaves. The leaves will appear spotted and whitish. Unfortunately, the only way to get rid of a lacebug infection is to treat it with a pesticide. Treat the underside of each leaf if you notice your shrub has succumbed to this pest.
Another problem for mountain laurel is leaf spot. This fungal disease can often be prevented by purchasing a resistant variety and by providing plenty of sunshine and air circulation to your shrub. Prune your branches if that will help it breathe easier. Clean dead leaves away from the base of your mountain laurel, too. This can help to further prevent the spread of leaf spot to other leaves.
Mountain laurel is highly toxic to people and pets when ingested, so keep this in mind as you consider whether or not this shrub is right for you.
Varieties to Consider
- ‘Elf’ is a semi-dwarf variety with miniature leaf size. The blooms are nearly full size, which gives the shrub a whimsical appearance when in bloom.
- ‘Pinwheel’ has a compact form with hardy leaf structure that is resistant to leaf spot. The name is derived from the flowers which have scalloped edges. The center of the flower is white, and the tips are a deep red color which creates a striking contrast.
Common Questions and Answers About Mountain Laurel
by Erin Marissa Russell
Can you grow mountain laurel from cuttings?
Take cuttings to propagate mountain laurel from the current year’s growth between August and December. Treat the bottom of the stem where you took the cutting with rooting hormone and plant in a container filled with a mix of equal parts perlite, coarse sand, and peat moss. Water deeply and mist the leaves of the cutting after planting, then cover with a plastic bag propped over the container. Remove the plastic bag only to water and mist the cuttings each day. Keep soil moist, and find a spot that’s out of direct sunlight. Cuttings can take four to six months to develop roots.
Can you prune mountain laurel?
While only minimal pruning is needed for mountain laurel, you will occasionally need to prune back dead, damaged, or crossing branches, or you may need to create space for air to circulate and sunlight to reach the interior of the laurel’s branches. Cut the faded flowers off after the first bloom in spring to encourage your mountain laurel to bloom again. Perform maintenance pruning as well, though pruning to remove damaged branches can be done at any time. Use clean, sterilized gardening tools to prune your mountain laurel, sanitizing the tool between cuts if you’re removing diseased areas. Remove large, old branches that need refreshing as well as damaged, crossing, or diseased branches. Never remove more than one third of the plant at a time.
Can you transplant mountain laurel?
Transplant mountain laurel in the fall, between late August and late October. When you’re digging up the plants, remove as much of the root ball as you can get. Be careful to keep the soil clinging to the roots as much as possible. Water your mountain laurel plants well for a year after transplanting, and add a layer of mulch such as pine needles or shredded hardwood on top of the root zone.
Do mountain laurels bloom every year?
Mountain laurels bloom yearly in mid to late spring, displaying flowers in shades of pink to white.
How big do mountain laurels get?
When cared for properly, mountain laurels can reach heights between six and 20 feet.
How do you propagate mountain laurel?
Propagate new plants from your established mountain laurel by making a cutting between August and December from the current year’s growth. Treat the bottom end of the cutting with rooting hormone, and plant in a container filled with a mix of equal parts perlite, coarse sand, and peat moss. Water the cutting deeply after planting and mist its leaves, then place an upside-down plastic bag over the top of the container to keep soil moist. Only remove the plastic bag to water or mist the plant each day. Keep the soil moist while the cutting grows, and find a location for the container that is out of direct sunlight. Cuttings will develop roots in four to six months.
Should I deadhead mountain laurel?
You can deadhead mountain laurel by cutting back the foliage with faded blooms after the first bloom of the season has expired. Deadheading will encourage the mountain laurel to bloom again.
Will mountain laurel grow in full sun?
Mountain laurel prefers to grow in locations that get dappled sunlight, but the plants can tolerate either full sun or partial shade. Avoid spots that get full sun and reflect light and heat from southern-facing or southwestern walls. In especially hot climates, partial shade is best for mountain laurel.
Want to learn more about Mountain Laurel?
TRIB Live covers Mountain Laurel a Delicate Shrub
Bay Weekly covers Give Rhododendrons and Mountain Laurel a Head Start
the Spruce covers Mountain Laurel Growing Tips
Kalmia Latifolia – University of Connecticut
Mountain Laurel (video) – Land Designs Unlimited