The boxwood, belonging to the genus Buxus, is a popular ornamental plant valued for its dense, evergreen foliage. It has been a mainstay in garden design for centuries, offering year-round structure and color to landscapes. Renowned for its ability to be precisely shaped, boxwood is a recognizable broadleaf evergreen, often used in formal gardens and public spaces.
Classification and Growth Habit
The genus Buxus is classified within the family Buxaceae and includes approximately 70 species native to Europe, Asia, Africa, and the Americas. While some varieties can reach heights of up to 20 feet, leading to confusion about them being “trees,” boxwoods are botanically categorized as multi-stemmed, broadleaf evergreen shrubs.
The growth habit is characterized by dense, often rounded branching that starts low to the ground. Boxwoods are generally slow-growing, which contributes to their dense foliage and allows them to maintain a specific, manicured size or shape over time. This slow growth means they require less frequent pruning than many other shrubs, making them ideal for formal landscaping applications.
Essential Identifying Characteristics
Boxwood plants are easily identified by their distinct leaf structure. The leaves are small, simple, and typically oval or elliptical in shape, measuring between 0.5 and 1.5 inches long. They are arranged in opposite pairs along the stems, which helps distinguish boxwood from similar plants like Japanese holly.
These evergreen leaves have a somewhat leathery texture and a glossy, dark green color on the top surface. A unique feature is the presence of small, dense white hairs, known as pubescence, along the midrib on the underside of the leaf.
The wood itself is exceedingly fine-grained, hard, and heavy. Historically, this dense wood was prized for fine carving, wood engraving blocks, and musical instruments because it lacks the typical visible growth rings of many other timbers.
The most common types seen in landscaping include the European boxwood (Buxus sempervirens) and Asian species like the Japanese or Korean boxwood (Buxus microphylla). European varieties tend to have a more pointed leaf tip, while Asian varieties often display a rounded tip with a slight notch. Asian types are typically more cold-tolerant and faster-growing, whereas the European species is known for its classic, dense habit.
Landscape Uses and Basic Cultivation
Landscape Uses
The boxwood’s dense foliage and tolerance for heavy shearing make it a preferred plant for formal garden design. It is frequently used for creating hedges and edging to define borders and pathways. The ability to hold its shape also makes it ideal for topiary, where it is sculpted into precise geometric forms like globes, cones, or spirals.
Planting Requirements
Boxwoods require well-drained soil to prevent root rot, as they do not tolerate consistently soggy conditions. They thrive best in a location that provides partial or dappled shade, especially in warmer climates where protection from intense afternoon sun is beneficial. While they can tolerate full shade, too little light can result in a less dense and more open habit.
Soil and Watering
The ideal soil pH for boxwood is neutral to slightly alkaline, ranging from 6.5 to 7.5. Because they are shallow-rooted, a layer of organic mulch around the base helps to keep the roots cool, conserve moisture, and suppress weeds. Established plants need regular watering, especially during dry periods. Deep watering before extreme cold spells is recommended to help prevent winter foliage bronzing and dehydration.