The term “laurel” is a common name applied to several distinct evergreen genera in landscaping, which makes understanding their mature size a challenge. These plants are frequently used for hedges and screens, so their ultimate height is a major consideration for homeowners. This article provides a look at the maximum expected dimensions of the most popular garden laurels and the environmental factors that dictate their actual growth. Knowing the difference between the species is necessary to accurately predict how tall a laurel will eventually grow.
Defining Common Garden Laurel Varieties
The most popular garden laurels originate from three distinct plant families, leading to significant variations in growth habits. Cherry Laurel, or English Laurel, belongs to the Prunus genus, which also includes cherries and plums. This group (Prunus laurocerasus and Prunus lusitanica) is characterized by glossy, broad, evergreen leaves and a vigorous growth rate.
Bay Laurel (Laurus nobilis) is the only plant commonly grown that is considered a “true” laurel, belonging to the family Lauraceae. This species is the source of the culinary bay leaf and is native to the Mediterranean region. It is typically grown as a pyramidal shrub or small tree in temperate climates.
The third major group is Mountain Laurel (Kalmia latifolia), a striking flowering shrub native to the eastern United States. Part of the Ericaceae family, it is a relative of rhododendrons and azaleas, which explains its requirement for highly acidic soil. Identifying the specific variety is the first step toward determining its mature height and spread.
Mature Height and Spread Metrics
The common species of Cherry Laurel (Prunus laurocerasus) is fast-growing and can reach substantial dimensions if left untrimmed, typically maturing between 15 and 30 feet tall with a similar spread. Many popular cultivars are selected for compact size. ‘Otto Luyken,’ for instance, generally stays around 5 feet tall but spreads 6 to 10 feet wide. ‘Schipkaensis’ offers a moderate size of 4 to 6 feet tall and 6 to 8 feet wide, making it suitable for smaller hedges.
Portuguese Laurel (Prunus lusitanica), which features reddish stems, commonly reaches 10 to 25 feet in height. In favorable conditions, this tree-like shrub can exceed 30 feet tall with a spread of 10 to 15 feet. Its moderate growth rate of one to two feet per year means it takes longer to reach maximum size than the quicker-growing Cherry Laurel.
Bay Laurel (Laurus nobilis) is slower growing, adding only 8 to 16 inches annually, but it can eventually become a large tree, reaching 10 to 30 feet tall and wide. In optimal conditions, it may grow up to 40 feet tall with a spread wider than 25 feet. Mountain Laurel (Kalmia latifolia) is a much smaller plant, generally maturing as a dense shrub 5 to 15 feet tall and wide. Wild specimens in the Appalachian Mountains have been recorded up to 30 feet, demonstrating the impact of native environments.
Environmental Conditions Affecting Growth Potential
A laurel’s actual height results from its genetic potential interacting with the growing environment. Sunlight exposure influences the plant’s structure; while most laurels tolerate partial shade, insufficient light causes the plant to become “leggy,” stretching vertically for sun, resulting in a taller but less dense form. Full sun encourages bushier, more compact growth, though intense afternoon sun can cause leaf scorch in some varieties.
Soil conditions, particularly drainage and pH level, directly influence nutrient uptake and plant vigor. All laurels require well-drained soil, as waterlogged roots quickly lead to root rot and stunted growth, often signaled by yellowing leaves. Mountain Laurel, a member of the heath family, thrives in acidic soil, while Portuguese Laurel tolerates chalky, alkaline conditions.
The hardiness zone and water availability establish the limits of a laurel’s growth. If a plant is at the colder edge of its temperature tolerance, it expends energy on survival rather than growth, resulting in a smaller final size. Consistent soil moisture is necessary for the rapid growth rates of Cherry and Portuguese laurels. Drought conditions severely restrict the plant’s ability to reach its maximum potential height.
Techniques for Size Management
Maintaining a laurel at a specific size requires consistent and proper pruning, preventing it from reaching its mature height. For formal hedges, especially Cherry Laurel, pruning should occur immediately after the spring flowering period to encourage dense, lateral branching. Regular trimming is important because the size of the canopy is directly related to the root system. Consistent pruning helps limit the plant’s size.
Size reduction or rejuvenation of an overgrown laurel is best performed in late winter or early spring before the new season’s growth begins. This hard pruning involves cutting thick, old branches back to a healthy side shoot or to ground level. This stimulates vigorous new growth from dormant buds. For hedging, use hand pruners or secateurs rather than hedge shears on broad-leaved laurels. This avoids cutting the large leaves in half, which leaves unsightly brown edges.
The method of pruning dictates the final shape and size of the laurel. Selective thinning, where individual branches are removed, maintains a more natural, tree-like form and promotes air circulation. Shearing, which involves uniform cutting across the entire surface, is the preferred method for creating a dense, formal hedge. This effectively keeps the plant contained at a predetermined height and width.