Is the growing height of a Korean Wintergreen Boxwood planted in a square planter box limited by the size of the planter box?
I understand Boxwoods are perfect for containers and the guideline is to plant Boxwood in a pot as "wide as the plant is tall". I wish to plant a pyramidal Korean Wintergreen Boxwood, which I understand has a growing habit 4' x 4', in an outdoor planter box. Unfortunately, the size of my available outdoor space will limit the size of my planter box to approximately 22"-26" square x 24" tall. Assuming proper plant care, can I expect the height of the Boxwood to achieve its 4’ potential, and the plant to remain healthy over time, even though my planter box can be no greater than 22” – 26” square?
Certified GKH Gardening Expert
This really depends. The largest size is governed by open planting. Then the container size is adjusted until it is no longer able to obtain full stature. With that being said, if you are planting one that is not fully established, then you may find that it will not get to full size. This does not mean that it will not grow properly, only that it may be slightly smaller in stature.
If this is a mature shrub, and you go to transplant, then you will have to prune the root space to fit, and keep it trimmed once every couple of years. It can maintain size with similar care to a bonsai, although, not at extreme.