What is the lotus?
The lotus flower is an exquisitely beautiful plant native to South and East Asia. It is sacred to Hindus and Buddhists, for whom it symbolises enlightenment, and also the national flower of India and Vietnam.
The lotus is a rare example of a plant that can regulate its temperature. The flowers generate heat internally and can reach 20°C above the air temperature, which may help the plant attract insect pollinators.
What is the lotus effect?
That, though, is not the lotus effect. The term lotus effect describes the spectacular water-repellent and self-cleaning properties of the lotus plant's leaves.
Like other plants, the lotus takes in carbon dioxide and emits oxygen via minuscule pores called stomata. In most plants, these are on the leaves’ underside, where they are protected from being blocked by rain or airborne dust.
But the underside of a floating leaf is not exposed to the air, so the lotus’s stomata have been relocated to the top, which is kept clean and dry thanks to the leaves’ microscopic surface texture, which was discovered following the development of the electron microscope.
Finger-like projections, each less than 10-millionths of a metre thick, minimise the area of contact between the leaf and any surface water, causing it to form beads rather than spread out evenly. The effect is amplified by clusters of even smaller fingers of water-repellent wax. The slightest disturbance is enough to cause the droplets to roll off the leaf, taking dust, dirt, fungal spores and algal growths with them.
This surface texture gives lotus leaves a matt, velvety appearance, which is characteristic of other hydrophobic plants such as nasturtiums, ginkgo trees and lady’s mantle. The effect is also a feature of insect wings and the skin of some geckos.
The lotus effect has inspired the development of synthetic self-cleaning textiles and low-friction swimming costumes. There are also ambitions to engrave the hulls of boats with lotus-like micro-textures to reduce drag and prevent the attachment of encrusting organisms.
Perhaps this unusual plant is worthy of a place on our weirdest plants in the world list?
Learn more fascinating plant facts