The Maranta leuconeura, or Prayer Plant, is a popular houseplant native to the tropical forests of Brazil. It is known for its attractive, oval foliage, which often features deep green, red, and purple markings. The common name, Prayer Plant, refers to a striking daily behavior: the movement of its leaves over a 24-hour cycle.
The Movement That Inspired the Name
The plant’s common name stems from a leaf movement that occurs as the sun sets. During the day, the leaves of the Maranta leuconeura lie flat and horizontal to maximize sunlight collection, which is important as they grow in the shaded rainforest understory.
As evening approaches and light levels decrease, the leaves begin a slow, upward folding motion. They rise and close together, resembling hands folded in prayer. This upward posture is maintained throughout the night until morning, when the leaves slowly unfold and return to their flat position. This distinct cycle of opening and closing inspired the common name upon the plant’s introduction to Western culture.
The Science Behind Leaf Movement (Nyctinasty)
The leaf movement is a form of plant behavior called nyctinasty, which translates to “sleep movement.” Nyctinastic movements are routine, reversible responses to the daily change in light and dark conditions. The movement is controlled by the plant’s internal circadian rhythm, or natural 24-hour clock, which works with environmental light cues.
The mechanism is centered in a specialized, joint-like structure at the base of the leaf called the pulvinus. The pulvinus is composed of motor cells that change size and shape to facilitate the motion. This change is driven by the movement of water into and out of these cells, altering their internal water pressure, known as turgor pressure.
During the day, high turgor pressure in the cells on the underside of the pulvinus holds the leaf open. As night falls, the plant shifts ions out of these cells, causing water to follow by osmosis. This loss of water decreases turgor pressure, forcing the leaf to fold upward. The reverse process occurs at dawn, restoring the pressure and returning the leaf to its open posture.
Essential Care for the Prayer Plant
Caring for the Prayer Plant involves replicating the warm, humid conditions of its native tropical environment. The plant thrives in bright, indirect light, which mimics the filtered sun it receives beneath the rainforest canopy. Avoid direct, intense sunlight, as it can scorch the leaves and cause colors to fade.
Maintaining consistently moist soil is important, but the plant should never be left waterlogged, which leads to root rot. Water thoroughly once the top inch of soil feels dry. Since these plants are sensitive to chlorine and fluoride in tap water, using distilled or filtered water can help prevent brown leaf tips and edges.
High humidity is a requirement for Maranta leuconeura; low humidity often causes browning or curling leaves. Placing the plant near a humidifier or on a tray filled with pebbles and water helps create the necessary moist microclimate. Keep the temperature stable, ideally between 65°F and 80°F.