In recent years Japanese willows, especially the dappled varieties with white to pink variegation, have become extremely popular landscape plants. Like most willows, they also grow extremely fast. As a garden center worker and landscaper, I have sold and planted hundreds of these trees. However, with every single one, I have warned the homeowner that it will not stay small and tidy for long. Trimming Japanese willows is a chore you may have to do several times a year to keep the shape and size in check. Continue reading to learn how to prune Japanese willows.
About Japanese Willow Pruning
All too often homeowners realize that cute little willow with the pink and white foliage can quickly become an 8 to 10 foot (2-3 m.) monster. As they grow and age, they can also lose a lot of the unique foliage colors that drew your eye to them in the first place. Fortunately, with regular pruning and trimming, the size and shape can be maintained. Pruning Japanese willows will also encourage new colorful growth.
A very forgiving plant, if necessary, you can cut back a Japanese willow to the height of about 12 inches (31 cm.) to let it rejuvenate and to try to keep a better handle on its future size and shape. With that being said, do not panic or stress too much about pruning a Japanese willow. If you accidentally cut off a wrong branch or trim it at the wrong time, you will not hurt it.
Even so, there are some recommended guidelines for Japanese willow pruning.
How to Cut Back a Japanese Willow Tree
Pruning of old, damaged, dead, or crossing branches to increase sunlight or air flow is generally done in late winter when the willow is dormant and the spring catkins have not yet formed. Cut these branches right back to their base. At this point, it is alright to remove about 1/3 of the branches with clean, sharp pruners or loppers.
Midsummer is an ideal time for trimming Japanese willows to shape, control size, and rejuvenate their variegation when the white and pink coloring of dappled willows tends to fade. However, some light to heavy trimming will cause the plant to send out colorful pink and white new growth.
It is usually recommended that you cut back a Japanese willow by about 30 to 50% but, as stated above, if the size and shape has really gotten out of hand, you can cut the whole plant back to about a foot (31 cm.) tall.