Calatheas (and Marantas) are called prayer plants because their leaves move up and down throughout the day. This prayer movement, called nyctinasty, is a circadian response to changes in light and Low light Tropical Living Art Florafelt Living Wall Systems Caput Medusae (Beginner Friendly!) Nothing makes you realize how big a ponytail palm can get until its time to repot one. Fresh soil, a bigger pot, and a whole lot of lifting later this giant is ready to keep growing .,