Ligustrum, commonly known as privet, is a versatile and popular shrub used widely in residential and commercial landscapes, primarily for creating dense hedges and privacy screens. The success, density, and long-term health of any Ligustrum planting are directly tied to the distance between each individual shrub. Determining the correct spacing is the most important decision before planting, as it dictates whether the plants will grow together seamlessly into a uniform barrier or stand alone as distinct specimens.
Spacing Goals: Hedges Versus Individual Shrubs
The philosophy behind spacing Ligustrum depends entirely on the desired outcome for the planting. The two primary goals, a dense hedge or an individual specimen, require different approaches to plant placement. When the objective is to form a continuous, impenetrable screen, the plants must be positioned closer together than their mature width to force interwoven growth. This close spacing encourages competition for sunlight, which compels the plants to grow vertically and fill in horizontal gaps, creating a thick barrier from the ground up.
A general rule for forming a fast, dense hedge is to plant each shrub at a distance equal to one-third to one-half of its anticipated mature spread. Conversely, if the goal is to cultivate a Ligustrum as a stand-alone specimen, spacing must accommodate the plant’s entire mature width. Providing ample space ensures the shrub receives sufficient air circulation, which helps reduce the risk of fungal diseases.
Determining Spacing Based on Ligustrum Variety
Translating the general spacing rules into actionable measurements requires considering the mature dimensions of the specific Ligustrum variety being planted. Different species and cultivars have significantly different mature spreads, directly influencing the appropriate distance between plants.
Japanese Privet (Ligustrum japonicum)
This variety typically matures to a spread of 6 to 8 feet wide. For a dense, uniform hedge, plants should be placed 3 to 4 feet apart on center. If the goal is a specimen planting, it should be situated at least 8 feet away from other large shrubs or structures to allow for its full mature width. The Waxleaf Privet (L. japonicum ‘Texanum’), with a slightly smaller mature spread of about 6 feet, can be planted as close as 18 to 24 inches apart for a highly formal, tight hedge.
California Privet (Ligustrum ovalifolium)
Known for its suitability for formal hedges, this variety tolerates extremely close planting. With a mature spread ranging from 6 to 10 feet, it is often planted as tightly as 9 to 15 inches apart in a single row to quickly create a dense, narrow screen. This tight placement necessitates frequent, heavy pruning but achieves a solid barrier rapidly.
Glossy Privet (Ligustrum lucidum)
This larger variety can function more like a small tree, reaching a mature spread of 8 to 15 feet. For a tall, dense screening hedge, these shrubs should be spaced 4 to 6 feet apart to allow for the significant interweaving of their broader canopies. If grown as a standard tree form, a minimum of 15 feet of clearance is necessary.
The growth rate of the chosen variety also plays a role in the decision. Closer spacing facilitates quicker hedge formation but requires more frequent maintenance pruning. Faster-growing types will fill in the gaps sooner, but the increased density will demand more regular trimming to maintain shape and prevent overcrowding.
Practical Planting and Establishment Care
Once the appropriate spacing has been determined, proper planting technique is paramount to ensure the Ligustrum establishes a strong root system. The planting hole should be dug at least twice as wide as the root ball but no deeper than the height of the root ball itself. Digging the hole wider allows new roots to easily penetrate the surrounding native soil; planting too deep can lead to stem rot and suffocation of the roots.
Before placing the shrub into the ground, inspect the root ball for any circling or girdling roots, which are common in container-grown plants. These roots must be loosened, gently pulled outward, or scored with a knife to encourage them to grow horizontally into the surrounding soil. The shrub should be positioned so the root flare—the point where the trunk widens at the base—is level with or slightly above the surrounding soil grade.
After backfilling the hole with the original, unamended soil and gently tamping it to remove large air pockets, the newly planted Ligustrum requires an immediate and thorough watering. This initial deep irrigation settles the soil completely around the roots. For newly planted hedges, immediately perform a light shaping or cut back the top one-third of the plant’s height. This initial pruning encourages the development of lateral branching, which is necessary for achieving the dense, bushy appearance required for a successful privacy screen.