
One thing about growing bamboo: you never have a
shortage of plant stakes. If you want your stand of medium-to-large
bamboo to thrive, you will have to do some thinning anyway. Bamboo
culms reach their peak as timber after the second growing season,
and the culms of most species lose vigor and start to die after three
or four years. Thinning removes the worn-out culms and lets light
into the center of the clump to encourage new culms.
The best method of thinning is to select culms at least two years
old and harvest them by cutting them close to the ground with a pruning
saw. Open up the stand to encourage new culms all through the clump
rather than just around the periphery. Then trim the branches off
the harvested culms and and set the culms aside to dry into poles.
If you want to use the bamboo in craft projects or as building material,
keep in mind that it is much easier to work green; do any shaping
or bending before it dries.
While mature stands often branch for just the top one-third of the
culm, younger plants tend to have branches right down to the ground,
giving your bamboo a shrubby look. For appearance's sake you may want
to trim off the lower branches; the easiest way is to cut out the
bud at each node as it begins to swell. Doing so will give you smooth
bamboo poles without branch stubs. Use a sharp knife to remove the
bud callus as it begins to thicken. Another option is to clip off
the branches with pruning shears. If you use the poles as supports
for beans or other climbing plants, the branch stubs offer a hold
for the tendrils.