The cherry laurels of the genus Prunus will be discussed in detail. Laurel or sweet bay (Laurus nobilis) and mountain laurel (Kalmia latifolia) are briefly mentioned.
Cherry Laurel or English Laurel (Prunus laurocerasus)
Mature Height/Spread: This evergreen, broadleaf shrub can grow to 20 feet but is generally kept smaller in the home landscape. The spread is 6 to 10 feet. The leathery, glossy, dark green leaves are 3 to 7 inches long and 1½ to 2 inches wide. Cherry laurel blooms in mid spring and has white flowers, which are often hidden by the leaves. Small black fruits appear in the fall.
Growth Rate: Cherry laurel is a fast-growing plant. It grows 25 inches or more per year.
Landscape Use: Suggested uses for this plant include hedges and groupings. It is very popular in the South.
Cultivation: Cherry laurels perform best in moist, well-drained soil supplemented with organic matter. Plant in partial shade to full sun. This plant tolerates salt spray and heavy shearing. Avoid excessive fertilization.
Problems: Cherry laurel is more disease- and insect-resistant than other Prunus species, but root rot can be a problem if the shrub is planted in a wet location. A fungal or bacterial disease called “shot hole,” produces purple to reddish leaf spots. The spots drop out, leaving circular holes in the leaf. Mild, wet summer weather promotes this leaf spot. Avoid overhead watering. The fungus Botryosphaeria causes limb dieback.
Cultivars & Varieties
‘Otto Luyken’ grows 3 to 4 feet high and 5 to 7 feet wide. The foliage is glossy, dark green, the flowers are white, and the fruit is black.
‘Schipka laurel’ (Schipkaensis) is a spreading shrub, 4 to 5 feet tall and 5 to 8 feet wide with dark green foliage, white flowers and black fruit. This shrub has a refined appearance and is hardy and vigorous in habit of growth.
‘Zabel laurel’ (Zabeliana) is a narrow-leafed cultivar with branches angling upward and outward (5 to 8 feet) from the plant base. The shrub grows 5 to 6 feet in height and is more tolerant of full sun than the species.
Carolina Cherry Laurel (Prunus caroliniana)
Carolina cherry laurel can reach 35 to 40 feet with multiple trunks. Often it is used as a clipped hedge or tall screen to 20 feet high. The densely leaved plant has glossy green leaves, which are 2 to 4 inches long. Small, white flowers appear in late winter or spring, followed by black fruit almost the size of blueberries. This shrub is tolerant of heat and drought.
Portugal Laurel (Prunus lusitanica)
Portugal laurel is a densely branched shrub, 10 to 20 feet tall, or a multitrunked, spreading tree up to 30 feet tall. When trained to a single trunk, it is used as a formal street tree. The glossy, dark green leaves are 5 inches long by 2 inches wide. Small, white flowers in 5- to 10-inch spikes appear in spring and early summer, followed by clusters of tiny, red to dark purple fruit. Portugal laurel is slower growing than cherry laurel, but more tolerant of heat, sun, wind and drought.
Laurel or Sweet Bay (Laurus nobilis)
This attractive, evergreen tree grows 10 to 12 feet with a spread of 8 to 10 feet. The thick, leathery, dark green leaves are 2 to 4 inches long and 1 inch wide, with wavy margins. The greenish-yellow flowers are without petals and not very ornamental. The bark is gray, and the fruit is a black berry.
Bay trees grow slowly. They prefer full sun to light shade and fertile, well-drained soil. They can be used as topiary, hedge or screen. Bay leaves can be harvested and dried throughout the year. This ancient and famous plant may not survive winter in the Upstate, but it grows well in the Coastal Plain. Bay trees are susceptible to white wax scale, which makes the leaves sooty and retards leaf growth.
Mountain Laurel (Kalmia latifolia)
This broadleaf evergreen shrub grows to a height of 12 to 15 feet and spreads to 12 feet. The growth rate is less than 12 inches a year. Mountain laurel requires an acid, well-aerated soil. It tolerates shade, but some exposure to sun is required for proper flower color development of red and pink cultivars. The foliage is thick and leathery with a dark green color at maturity.
Mountain laurel is native to dry rocky woodlands, slopes and streambanks from Florida to Canada. This shrub can be used in borders, foundation plantings, screen, massing and as a specimen plant. Mountain laurel’s cultural requirements are similar to those of rhododendron and azalea, so they can be grown together.
Mountain laurel is susceptible to scale insects, lacebug, whitefly and borers. Cercospora leaf spot is found on almost all mountain laurels. This fungus causes irregular to circular spots on the leaves of mountain laurel throughout the Appalachian region. Severe infection seems to stunt plant growth and suppress flowering, particularly on plants growing in moist, shady places. The spots are 2 to 4 inches across, at first medium to dark brown on both surfaces, but fading to grayish brown in the center of the upper surface. The margin remains dark brown to purplish brown.