Repotting a Castillon bamboo: lesson learned

Since our backyard is so small, all our running bamboos are confined to containers. Planted in the ground, they would require careful monitoring to ensure that they don’t escape under the fence into a neighbor’s yard. While I do keep a good eye on things, I’d rather not have to worry about potential bamboo problems.

The downside about keeping taller bamboos in containers is that they get pot-bound fairly quickly. To keep them healthy, you need to remove them from the pot every year or so and remove the rhizomes that will invariably have started to circle around the root ball. In addition, potted bamboos need extra watering because a great deal of moisture evaporates through the leaves.

Our potted bamboos are tied into an automatic drip system. It usually runs from April through late October, i.e. during our dry season. In the late fall through early spring, we get enough rain to keep things hydrated. In a normal year, that is. This winter has been exceedingly dry, about 40% of normal. While I’ve manually turned on the drip a few times, I’ve been lax about it lately. I noticed the other day that our Castillon bamboo (Phyllostachys bambusoides ‘Castillon’), a beautiful running bamboo with green-striped golden culms and variegated leaves, is looking parched. Instead of simply watering it, I decided to kill several birds with one stone: remove the bamboo from its current pot, do some rhizome pruning, and move it into a larger pot.

Phyllostachys bambusoides ‘Castillon’ (in red pot)

Leaves on the verge of drying out

With my wife’s help, I laid the old pot on its side and then carefully pulled out the bamboo. I expected quite a bit of resistance, and I was shocked by how easily it slid out—and how light it was. It was clear the root ball was almost completely dry.

Nice roots but not enough moisture

Rhizomes circling around the pot. I cut them off before replanting the bamboo.

I removed the rhizomes that had encircled the root ball, trimmed off some smaller culms as well as some lower-growing branches, and then plopped the plant into its new pot. After I filled in dirt mixed with slow-release fertilizer, I watered the bamboo thoroughly. Hopefully within a month there will be new leaves to replace the ones that have dried up. Fortunately, bamboos are very forgiving as long as you don’t let them go completely dry.

                                                                                                                                                  
 

New pot, new spot

I’m hoping that in a year or two the new culms will be tall enough to give us added privacy

What remains after I removed the oldest (and smallest) culms and the lower branches

I’ve definitely learned my lesson. Just because it’s winter and Mother Nature is supposed to provide us with water, we can’t take anything for granted. Gardeners can never allow themselves to become self-complacent!