Hi all -- I have bought three himalayan birches and I would like to know how close to each other they can be planted. I read 5-6 feet on one website. Can they be planted closer together? Many thanks, Laura
Sure you can plant them closer if you want. The recommendation was for the trees canopy most likely. Beware of stressing a birch tree! Particularly in the lower mainland where they are attacked by the bronze birch borer. I have found that proper irrigation during times of drought works the best. The borer doesn't like to tunnel in wet sappy cambium. (this also worked on pine trees in the interior)
Birch clumps planted in the open do not work because the trunks lean away from one another over time, to produce a visual tension. Where these can be successful is within a larger grove of more widely spaced birch trees, that will shade the clump from the sides and keep its trunks growing upward, toward the light.