Pruning boxwood, know it all

Boxwood pruning

Running contrary to popular belief, the pruning of boxwood is actually very easy, and doesn’t endanger your shrub in the least.

Pruning boxwood is a practice that helps shape this magnificent shrub, while giving it a chance to renew its leaves and grow denser than ever before.

Don’t be afraid to prune it, this will also make the plant more vigorous!

Season for trimming boxwood

  • For those boxwood shrubs shorter than about 3 feet (1 meter): the best time to prune is around April-June and August-October.
    So, in short, they are pruned twice, and a tip to remember this is that these are the “A” months, from the letter that the month begins with.
  • It is possible to prune during other months, too, but not in winter nor during the vegetation phase of your boxwood.
  • For boxwoods that form a hedge and aren’t being modeled into any specific shape, pruning once before summer is enough.

Note, however, that in some places, for some types of hedges, trimming is unlawful in Spring. This is to ensure birds aren’t disturbed during the nesting season.

Tools needed to prune boxwood

  • Special scissors or shears have been developed for pruning topiary, they are perfect for boxwood.
  • For hedge-bound boxwood, any hedge trimmer or long-bladed shears will do fine.

Giving your boxwood a round, conical or other shape

  • During the first year, start giving your boxwood the shape you’re aiming for.
    At the beginning, simply go for the general silhouette rather than pruning in great detail.
    It will take you several years before you’ll make it to the final shape.
  • Afterwards, every time you prune, you’ll only remove a portion of the new growth added since the previous pruning.
    As time goes by, your shrub will grow in size but retain the shape that you wish it to have.

Pruning a boxwood hedge

  • Using a guide makes pruning straighterIn a hedge, it is important that the lower portion of the hedge be wider than the top, kind of like a narrow pyramid with a cut top.
    That is how the entire shrub will receive sufficient light.
    If the lower part is thinner than the top, it will grow sparse.
  • For low-lying hedges, set one plant every 4 to 6 inches (10 to 15 cm), to ensure full density.

Hard pruning of boxwood

Has your boxwood grown too large? Reduce it to the size you need over a few years with the following technique:

  • Early Spring, cut one in two or one in three branches back to about a foot shorter than your target size (30 cm).
  • This will make the boxwood look like a swiss cheese with lots of light reaching the center.
  • New branches will sprout in the center of the shrub.
  • In Spring of the following year, you can cut back the remaining branches.
  • From then on, you can trim and prune your boxwood regularly to keep it at a manageable shape.

Cutting the entire tree back in one go might kill the shrub, which is why it’s best to stage it over at least two years (ideally three).

Some people recommend cutting back to a stump. Though some box shrubs do recover, it isn’t at all guaranteed. The gradual reducing of the shrub will make sure it survives.

Read also on pruning and boxwood:


Image credits (edits Gaspard Lorthiois):
CC BY-SA 2.0: La Citta Vita