My mom bought me a curly bamboo in a cute little ceramic pot. It said to keep moist, so I did that and used a little miracle grow and it did fine for about a year. A month ago, I noticed a yellowing of the bamboo stalk and a black speckled moldlike substance on the stalk. One of the stalks that had no leaves actually broke or rotted off. I don't know what I did wrong or how to save it. The leaves are still green but I don't think for long. Any help would be greatly appreciated! Thanks!