While most often used for formal hedges, boxwood specimens can be sheared into tight shapes such as cones and pyramids, globes, spirals, squares and other geometrical shapes. They are also nice for spiral, poodle tier, and other shapes for topiary. If you're looking to create a theme garden, boxwood shrubs are perfect for use as clipped or sheared hedges in formal gardens. Dwarf varieties make nice low border hedges in herb gardens, such as knot gardens.
Here's some tips for how to prune boxwood shrubs...
Pruning Boxwood Shrubs
As mentioned above, Boxwood shrubs do not require pruning but respond very well to it for shaping purposes.
When To Prune Boxwood
Selective pruning to remove a stray or damaged branch can be performed any time of year on Boxwood.
Shearing plants to form shapes or hedges can be performed almost any time of year. However, to avoid damaging new growth that typically emerges after pruning, cease pruning two months prior to the average first frost date in your area. When plants have gone dormant for winter pruning can resume.
Heavy pruning to create topiary shapes should be performed when the plant is in winter dormancy (not actively growing).
Selective Pruning of Boxwood
Use a sharp pair of bypass hand pruners to selectively remove stray, damaged or dead branches. Make your cut at a point along the branch just above the main form of the plant. Remove dead branches to a point a couple inches below their point of origin.
Shearing Boxwoods for Shape
Hedge trimmers, clippers or shears can be used throughout the active growing season to shape plants. Because most of the foliage is only at the ends of stems, it's better to lightly shear plants more regularly rather than to infrequently take off large amounts of foliage that can leave the shrub looking bare for quite some time.
Boxwood Topiary Pruning
Pruning a boxwood for topiary should be done in late winter, when the plant is still dormant (not actively growing).
Pruning Boxwood for topiary can be tricky, especially when the desired shape is a spiral or some type of animal form. If you're not a natural at carving 3-dimensional shapes and forms, it might be best to leave topiary pruning and shaping to an expert. Otherwise, if you're confident with your carving skills, go ahead and do it. Just make sure to draw out the desired shape on paper first.
Start your topiary by removing plant parts as necessary to achieve the desired shape. Before removing a branch or stem, check to make sure that doing so will not spoil the shape. Know that when removing large sections of the plant there will be some bare areas absent of leaves. New foliage should emerge when spring arrives.