Taxonomy of Privet Shrubs:
Plant taxonomy classifies privet shrubs under the genus, Ligustrum; indeed, they are commonly referred to as "ligustrum shrubs," too. Within the Ligustrum genus, there are various species and cultivars, some of which I'll mention below (see "Varieties of Privet Shrubs and Their Planting Zones"). Privet shrubs are so commonly used in hedges that they are often referred to as "privet hedges."
Depending on plant variety and the zone in which you live, privet hedges can be evergreen, semi-evergreen or deciduous.
Some Varieties of Privet Shrubs and Their Growing Zones:
- Common privet shrubs (Ligustrum vulgare): zones 5-8.
- Golden privet shrubs (Ligustrum ovalifolium 'Aureum'): zones 5-8
- Amur privet shrubs (Ligustrum amurense): zones 3-6.
- Japanese or wax privet shrubs (Ligustrum japonicum): zones 7-10.
- Chinese privet shrubs (Ligustrum sinense): zones 7-9.
Characteristics of Privet Shrubs:
Privet shrubs reach a height of 4'-15' with a spread of 4'-8'. They bear white flowers in late spring-early summer; berries succeed the flowers. But privet shrubs are grown primarily for the dense foliage they can provide when pruned into hedges.
Plant Care Tips for Privet Hedges:
Prune these bushes after they have flowered; thereafter, prune them an additional 3 or 4 times during the course of the summer. Privet hedges will fill in better (i.e., the plants will become bushier) if they are pruned frequently.
Sun and Soil Requirements for Privet Hedges:
Privet hedges prefer partial shade to full sun. Grow privet hedges in a soil that is slightly wet. Privet hedges tolerate a wide pH range.
Uses for Privet Shrubs in Landscape Design:
Privet shrubs are used almost exclusively to form hedges. Not especially beautiful plants when considered in isolation, privet shrubs do excel in the role of hedges. They grow more quickly and are more malleable than boxwood shrubs, for instance (another shrub widely used in hedges). Privet hedges tolerate heavy pruning and don't seem troubled by the pollution that plagues plants in urban settings.
Caveats in Planting Privet Hedges:
Despite the strong arguments just made for using privet shrubs to form hedges, privet shrubs do not come without drawbacks. First of all, they are poisonous. Secondly, since they are not evergreen in the North, privet hedges are attractive for only a portion of the year there. Finally, privet shrubs are invasive plants; many choose not to grow them for this reason alone.