Many of us appreciate boxwoods! They provide year-round color, dense foliage, and structure—plus, they are deer-resistant! However, these evergreen shrubs do benefit from some trimming. Learn how to plant, take care of, and prune boxwoods.
Boxwoods belong to the genus Buxus and are native to Europe and Asia. Broadleaf evergreens, they are relatively slow growers, meaning less work once they reach full size. Boxwoods have been popular for thousands of years and have been used in gardens as early as 6000 years ago.
While boxwoods are well-known for their use in formal gardens, they are much more versatile, with hundreds of variations in size, color, and shape. English Boxwood is probably the most popular variety in the home garden.
Boxwood hardiness zone is generally from 5 to 9, though a few cultivars are hardy to zone 4. They come in a range of shapes and sizes, ranging from 1 to 20 feet tall and 2 to 8 feet wide. Some boxwoods are suitable for topiary, and miniature versions are sometimes used in bonsai.
Most boxwoods tolerate shearing well, making them popular for creating dense visual barriers. They are fantastic choices for edging of paths and walks, creating garden rooms outdoors, and hiding the trash can. Boxwoods can be also used as sentinels guarding a gate or path entrance. Most boxwoods only grow 3 to 6 inches per year so they may not be the best choice if you need to grow a quick privacy screen.
What to Plant in Front of Boxwoods
Boxwood if often used as foundation plantings in front of a house. Their year-round green color nicely sets off colorful spring bulbs, annual flowers, and perennials. They also look wonderful mixed with flowering shrubs such as hydrangea or spiria and consider golden cypress and dwarf conifers.
Boxwoods enjoy partial sun, about 4 to 6 hours per day. They will tolerate full sun but like protection from the hottest rays in the afternoon. They are not picky about soil types and will do well with soil pH from slightly acidic to slightly alkaline.
Drainage is a must, however. Poorly drained sites are not suitable for these shrubs. Most species and varieties are hardy in USDA zones 5 to 9, although some hybrids are available that are hardy down to zone 4.
Boxwoods are susceptible to winter burn damage if planted in a windy spot. Plants on sites with a south or southwest exposure are most likely to suffer issues. To help reduce the chance of winter injury, provide a windbreak from harsh winter winds.
When to Plant Boxwoods
Like other trees and shrubs, the best time to plant boxwoods is in spring or early summer. Containerized stock can be transplanted throughout the growing season, but try to get them in the ground at least six weeks before the ground starts to freeze to let them establish their root system. In warmer climates, fall planting is also a possibility.
How to Plant Boxwoods
Boxwoods planted for a hedge or border planting need to be grouped closely together. Half the mature width apart will provide a dense, well-knit effect. Boxwoods that reach four feet wide at maturity should be planted two feet apart to provide that smooth, manicured privacy screen or border.
Plants that will be specimen or accent shrubs can be planted with standard spacing to allow air circulation and a more open, loose shape.
Dig a hole twice as wide as the rootball and slightly deeper. It should resemble a shallow bowl, not a well.
When setting the plant in the ground, the crown should be slightly higher in the soil than in the nursery pot. Planting boxwoods too deep can allow water ponding on the surface, which may lead to root rot issues. Place the rootball in the hole and adjust with soil until it’s at the correct depth.
If the roots are heavily circled or overgrown, you may need to loosen them first. Use a handheld garden tool to cut any girdling roots and loosen the root ball.
Set your boxwood in the hole and begin backfilling with the soil you removed. Be sure to firm the soil to eliminate air pockets around the roots.
Water your new plant well.
Mulch thickly, about 3-4 inches deep, around the base, but don’t mound the mulch around the stem. Mulch touching the stem can sometimes lead to rot and disease.
Taller, older shrubs purchased from a nursery may need staking for the first year, as they can be top-heavy.
Boxwoods don’t need much maintenance once they are established. Re-apply mulch to keep unsightly weeds down and maintain the soil moisture level.
During the first year, water regularly. They are relatively shallow-rooted and will need supplemental watering during hot, dry spells afterward.
Fertilize if desired in spring with a slow-release general-purpose fertilizer or one specifically for shrubs and ornamental trees. Avoid fertilizing in the fall. Don’t overapply–fertilizer will help your boxwood to be full and lush, but it won’t make it grow much faster.
When to Trim Boxwoods
Boxwoods can be lightly trimmed or sheared for shaping at nearly any time during the growing season. Avoid pruning in late fall as this encourages new growth which may be damaged by oncoming cold weather.
When to Prune Boxwoods
Boxwoods don’t need heavy pruning. If outer growth becomes too dense, selectively remove some of the older branches to improve air circulation and allow more light. Any heavy pruning of branches should be done in late winter or early spring before leavy growth. Dead, broken, or diseased branches can be pruned out any time.
With so many types of boxwood to choose from, it makes sense to narrow down the choices to fit your intended use. Pay attention to mature size, whether that’s small and compact or tall and imposing, as well as growth rates.
‘Graham Blandy’ (B. sempervirens) is a tall, columnar shrub that can reach 15 feet in height while remaining only 2-4 feet wide. An excellent choice for privacy fences and marking property borders.
Korean boxwoods (B. sinica) are smaller in size, with smaller leaves. Slow growers, they are sometimes chosen for bonsai.
Sprinter® boxwood (B. microphylla ‘Bulthouse’) is a compact, shorter shrub with a mature size of 2-4 feet tall. It makes a rounded shape with little effort and is one of the fastest-growing boxwoods.
Buxus sempervirens ‘Pyramidalis’ maintains a cone shape without trimming. Modest in size at 8-12 feet tall.
Wit and Wisdom
Boxwoods can be propagated from cuttings, easing the financial cost of establishing a larger border or hedge.
Yellowing leaves on boxwood can be caused by winter damage as well as root rot and drought stress. Otherwise, boxwood only has a few pests/diseases:
Boxwood blight (caused by the fungus Cylindrocladium psuedonaviculatum)