Known as the dancing plant, the telegraph plant is a tropical plant that dances as the leaves move up and down in bright light. Telegraph plant also responds to warmth, high frequency sound waves or touch. During nights, the leaves droop downwards. Telegraph plant is native to Asia. This low-maintenance, problem-free member of the pea family is usually grown indoors, surviving outdoors only in the warmest climates. Telegraph plant is a vigorous grower that reaches heights of 2 to 4 feet at maturity. Why Does a Telegraph Plant Move? The plant’s hinged leaves move to reposition themselves where they receive more warmth and light. Some botanists believe the movements are caused by special cells that cause the leaves to move when water molecules swell or shrink. Charles Darwin studied the plants for many years. He believed the movements were the plant’s way of shaking water droplets from the leaves after a heavy rainfall.