Privet (Ligustrum) is a widely planted shrub valued for its dense foliage, making it a popular choice for creating privacy screens and formal hedges. Known for its adaptability, privet establishes quickly in a landscape. Its rapid development is often the primary reason gardeners select it, as it forms a thick, green barrier in a relatively short period. Understanding the annual growth rate is important for planning its placement and managing its size, as the vigor of Ligustrum species dictates the necessary maintenance schedule.
The Annual Growth Rate
The growth rate of privet is classified as fast, with most common varieties adding substantial height each year. Under favorable conditions, species like California Privet (Ligustrum ovalifolium) and Common Privet (Ligustrum vulgare) typically grow between 1 to 2 feet (30 to 60 centimeters) annually. Some cultivars, such as Japanese Privet (Ligustrum japonicum), can exhibit more vigorous growth, sometimes exceeding 25 inches in a single season. When young, some varieties may reach a growth rate of up to 3 feet per year.
This rate of vertical expansion slows down once the shrub reaches its mature height or is subjected to regular, restrictive pruning. For example, while California Privet can reach 10 to 15 feet tall, maintaining it as a 6-foot hedge requires constant intervention. The initial years see the most dramatic increase in size as the plant focuses on developing its structure. After a few years, the plant’s energy shifts toward producing dense, lateral branching, which creates the thick barrier desired for hedging.
Environmental Factors Influencing Growth
The specific growth rate a privet achieves is determined by its local environment and available resources. Sufficient sunlight is a major determinant of growth speed; privet performs best when it receives at least four to six hours of direct sun daily. While the shrub tolerates partial shade, reduced light intensity leads to slower, less dense growth. Privet prefers well-drained soil and will suffer in areas where water pools or the soil remains soggy.
Privet adapts to a wide range of soil types, from sandy to clay-heavy, and flourishes across a broad pH spectrum (typically 6.0 to 8.0). Consistent moisture is necessary for vigorous development during the active growing season. Although established hedges exhibit drought tolerance, dryness slows stem elongation as the plant conserves resources. Applying a balanced fertilizer (such as a 15-5-10 or 15-5-15 blend) twice a year—in spring and late summer—provides the nutrients needed to sustain rapid growth.
Temperature and the length of the growing season, defined by the plant’s hardiness zone, also influence its yearly output. California Privet thrives in USDA Hardiness Zones 5 through 8, where the season allows for substantial new growth. Planting outside its ideal climate range may cause the shrub to dedicate energy to cold or heat survival, diminishing the annual growth rate. Optimizing these factors allows a gardener to accelerate the formation of a screen or moderate the plant’s development.
Managing Rapid Growth
Because of privet’s fast growth, routine maintenance is necessary to keep the shrub in a controlled shape. For formal hedges, this means shearing two to three times annually to maintain a crisp, dense form. The first cut typically occurs in late spring after the initial burst of growth, followed by subsequent trims through late summer. Frequent light trimming encourages the plant to produce a denser network of outer branches, thickening the screen.
When shaping the hedge, ensure the top is slightly narrower than the base, creating a subtle taper. This technique allows sunlight to reach the lower branches, preventing the bottom of the hedge from becoming sparse. For older or overgrown hedges, renewal pruning (or hard pruning) can be executed in late winter or early spring. This involves cutting the entire shrub back severely, often leaving only 6 to 12 inches of the main structure, which stimulates a flush of healthy new growth the following season.