The bay leaf tree, Laurus nobilis, is a versatile evergreen plant native to the Mediterranean region. It thrives in warm, temperate climates, where it can develop into a substantial woody specimen. Its dark green, leathery leaves are used as a culinary herb to infuse flavor into a wide variety of dishes. The size of this tree varies dramatically depending on where and how it is cultivated.
Maximum Height and Spread Potential
The bay leaf tree can develop into a full-sized tree in its native, unrestricted Mediterranean habitat or in optimal growing conditions within USDA hardiness zones 8 through 11. Laurus nobilis is capable of reaching heights of 40 to 60 feet.
It typically forms a dense, pyramidal canopy with a mature spread ranging from 15 to 20 feet. The tree has a slow to moderate growth rate, usually adding only 8 to 16 inches of height per year. Reaching maximum potential height takes many decades, which is why it is often seen at a more modest size of 10 to 30 feet, even when planted directly in the ground.
Management Through Pruning and Training
The bay leaf tree’s natural tendency to grow large is countered by its exceptional tolerance for sustained, heavy pruning. This characteristic allows gardeners to manage its size and shape, transforming it into a highly ornamental feature. The plant can be sheared and clipped to maintain it as a compact shrub or a dense, formal hedge.
Many growers utilize the bay tree’s dense foliage to create topiary forms. It is commonly shaped into a standard, or “lollipop” tree, with a clear single trunk supporting a tightly clipped spherical crown. Other popular shapes include cones, pyramids, or specimens with spirally trained stems. Size-controlling cuts are best performed during the summer months, though overgrown plants can be cut back hard in the late spring to rejuvenate them.
Size Restrictions Due to Environment and Containers
The plant’s size is naturally restricted by environmental factors outside of warm climates. The tree is not frost-tolerant and cannot survive prolonged freezing temperatures, making it unsuitable for year-round outdoor cultivation outside of USDA Zones 8 to 11. In colder regions, the tree must be grown in a container and brought indoors before the first frost.
The combination of root restriction and the stress of a less-than-ideal indoor environment limits growth. Confining the roots in a pot prevents the massive root system necessary to support a 40-foot tree, keeping the plant much smaller. Furthermore, when moved indoors for the winter, the tree is subjected to reduced light and humidity, which slows its growth rate. This passive size restriction is the primary reason why many home gardeners find their bay leaf tree remains a manageable specimen, rarely exceeding six to ten feet in height.