Calathea is a genus of neotropical rhizomatous herbaceous perennial plants; members of which are referred to generally as Calatheas. ‘Prayer plant’ is a colloquial term that refers to members of genus Maranta, to which genus Calathea is closely-related. In reality, they’re all considered to be ‘prayer plants.’Like a lot of low light plants, Calathea tend to grow fairly slowly. They are considered to grow at a moderately fast rate, but they will not grow and spread out over their pots and become a problem. In fact, Calathea plants usually will only grow to about 2 feet in height and then stop. After that, the only pruning you need to do is that of yellow, crispy, or brown leaves.