If you want a plant to delineate a formal bed, then contour into a topiary or form a dense privacy screen, Japanese box (Buxus microphylla japonica), or boxwood, is the own plant. Depending on how you prune this broadleaf evergreen, it can be casual or formal, permitted to rebound to 20 feet or remain a compact 2 feet tall. Suitable to U.S. Department of Agriculture plant hardiness zones 6 through 9, you can trim Japanese box nearly any time of year.
Japanese Boxwood
Japanese boxwood has small, oval leaves that are a deeper green than other boxwoods on densely packed branches. The shrub also creates clusters of tiny fragrant white flowers in spring. Japanese boxwood are known for having the ability to adapt to lighting conditions from full sun to full shade. In full shade the plants are water thrifty and can develop all summer without a supplemental water. Although boxwoods are slow-growing shrubs, Japanese box is the fastest growing number, reaching its adult size in three to five years. Mature plants require an annual pruning to maintain their shape or improve air flow.
Timing
Pruning prompts shrubs to put out new development. When pruned in late winter to early spring, this new growth conceals the cuts and helps the plant look fresh for the season. Since the plant grows during the summer, it can be sheared to get a neater look when you’re training it as a formal hedge. Any pruning should stop six weeks before the usual date of the place’s frost. This is because the tender leaf and stems that grow up from the pruned areas is susceptible to frost damage, which can cause leaves to blacken and stems to die back, although Japanese boxwood isn’t as easily damaged as alternative boxwood varieties. Dieback usually doesn’t happen in Japanese box unless temperatures dip to 10 degrees Fahrenheit.
Pruning Practices
Thinning is the recommended pruning way of maintaining Japanese box healthy while keeping a natural form. Thinning cuts remove small twiggy sections of dense outer growth down to the following side branch, allowing light into the center of the plant to prevent interior perish out. In older plants, you should remove one-third of the oldest or tallest branches at the base to shorten informal Japanese boxwood once it grows larger than you would like. Boxwood can also be maintained sheared into an official shape for a hedge or edging. Boxwood shrubs that are sheared from the time they’re implanted develop fetal growth. Shearing is best done in summer and whenever the plants begin to look scraggly, up to the six-week cutoff date. Sheared plants also require occasional thinning to open up them to light.
Considerations
Any lifeless, broken or crossing branches should be cut out at the base of the stem because they happen. Time shearing to eliminate flower buds should you find the strong scent of the flowers objectionable. Trimming in winter — when temperatures have cooled and the plant is dormant — can provide evergreen plant material for holiday decorating. Leave any cold-damaged growth on the plant until the late-winter pruning to avert the potential for further damage to the plant.