Black Shadow of Death on My Black Bamboo?
I'm quite anxious about this bamboo plant. I have two and they are both receiving roughly the same care, but this plant has limp leaves and two dead (nearly dead?) shoots. I'm worried of over/under-watering but don't know which might be the case. No leaves are dropping but that's the least of my worries as two entire culms might have .... dare I even say it. Oh, and we're currently raising these plants indoors in a sunny room in London. The other plant is healthy, robust, even bushy.
Hi Rodney, I'm far from expert on Bamboo, but I do have a small amount of experience with grasses, which are of course, related, but much smaller.
If you're concerned about over or underwatering, the first thing to check is that the pot they're in has a drainage hole. I don't know how many times I've seen that, where the most important feature of a container is completely missed.
Then, if it's possible, and the plant is well enough established, you might be able to carefully pull the pot right off the root ball. This will tell you right away if it's too wet or too dry, just by looking at the soil. Also carefully inspect the roots for any signs of rot (black or dark brown mushy roots) or any kind of uninvited visitor (grub or other creature).
If you can't see anything wrong with the roots or the soil, then it's possible the plant is in the direct path of a draft or air conditioning, or with the advent of cooler weather, possibly the forced air heater.
If you have natural gas heat, sometimes plants will warn you of a tiny leak even before you are aware of any problem. They're very sensitive to the chemical that is put into the natural gas to alert of a leak.
If none of these things seems to be what's causing the issue, then other things that might cause some problems are:
Over fertilizing, especially when the plant is dry.
Spider mites, aphids or other tiny insects - carefully inspect the undersides of the leaves.
More ominously, certain fungal or bacterial infections can get into the stem and in many cases, that's it for the plant. I would isolate it from the one that is still healthy, just in case there is something contagious going on.
Hopefully, one or more of these possibilities will be what is causing the plant to fail, and you can rectify it.
Best of luck with your Black Bamboo!