Codariocalyx motorius Seeds | Dancing Plant
LATIN NAME: Codariocalyx motorius
COMMON NAME: Telegraph Plant, Dancing Plant, Semaphore Plant
Plant Profile
Codariocalyx motorius is a tropical Asian shrub of the legume family, one to two metres tall, with three-parted leaves. The two small leaflets at the base of each leaf are the reason the plant is grown: they rotate through a slow circle, one rising as the other falls, several times an hour.
The movement is easy to see if the plant is warm and in good light. Each small leaflet is driven by a pulvinus, a swelling at the base of the stalk filled with water-pumped cells, and the oscillation continues for hours without any external trigger. Charles Darwin described it in 1880 in The Power of Movement in Plants, and it has fascinated physiologists ever since.
Science & Biotechnology
The rhythm is endogenous, not a response to touch. Cells in the pulvinus move potassium and chloride across their membranes, water follows, and the resulting change in turgor swings the leaflet. The cycle runs at one to four minutes in warm conditions and slows sharply as temperature falls.
The function is unresolved. Suggestions include moving the leaflets to expose them to light, discouraging herbivores, or simply being a by-product of a motor system that also drives the sleep movements all legumes show. There is no evidence that the plant responds to music, despite the common name dancing plant. The movement stops if the plant is repotted or chilled, and resumes a few days after conditions settle.
Uses & Benefits
The plant is sold as a curiosity and as a teaching subject. It has a modest place in local medicine in South-East Asia, where the leaf is used externally, but it is not a significant drug plant.
For growers, the appeal is watching a plant move without being touched. A warm room, bright indirect light and a pot that is not allowed to dry out will keep the leaflets active through the summer. The plant is not frost hardy and needs a minimum of about 15°C. A plant in a warm room will keep moving through the evening, though the swing slows after dark.
Growing from Seed
Seed has a hard coat and germinates unevenly. Nick the coat with sandpaper, soak for twelve hours, and sow at 25 to 30°C; germination takes ten to twenty days. Fresh seed is much better than stored seed.
Young plants want warmth, humidity and strong light, and they flower within three months of sowing in good conditions. The shrub is short-lived and leggy after a year, so cuttings or fresh seed are worth taking each spring. Stem cuttings root readily in water in summer, which is easier than raising it from seed each year. A light prune in early summer keeps the frame compact and produces the new shoots that move most strongly. Leaflets that stop moving are usually reacting to a cold draught rather than to disease.
Our Take
A genuine botanical curiosity, cheap from seed and worth growing once, provided you can keep it warm and give it light.
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