Kalanchoe – In Honor of Botanist Michael Adanson Who First Described the Genus
Kalanchoe is a group of about 125 species of succulent plants in the stonecrop family (Crassulaceae), most of them native to Madagascar and tropical Africa. The best known is the flaming Katy (Kalanchoe blossfeldiana), a cheerful houseplant covered in clusters of bright flowers.
Scientific Classification & Quick Facts
| Common name | Kalanchoe |
| Scientific name | Kalanchoe |
| Kingdom | Plantae |
| Phylum | Tracheophyta |
| Class | Magnoliopsida |
| Order | Saxifragales |
| Family | Crassulaceae |
| Type | Succulent flowering plant |
| Native range | Old World: Africa, Madagascar and Asia |
| Colours | Yellow, red, white or pink flowers |
| Flowering season | Spring |
| Height | Usually 15–45 cm; tallest up to 6 m |
| Special feature | A short-day plant that blooms on long nights |
Where Kalanchoes Come From
Around 60 kalanchoe species grow wild on the island of Madagascar, and many others come from eastern and southern Africa. A smaller number are found in Arabia and parts of southern and eastern Asia, including China. The French botanist Michel Adanson first described the genus in 1763. The name “Kalanchoe” is thought to come from a Chinese name for one of the plants.
Kalanchoes are also important to some insects. The caterpillars of the Red Pierrot butterfly, found in South and Southeast Asia, hatch on kalanchoe leaves and tunnel inside them as they feed.
What Kalanchoes Look Like
Like other succulents, kalanchoes store water in their thick, fleshy leaves, which helps them survive dry spells. Most species are small shrubs or perennials (plants that live for several years), while a few are biennials. The largest, the felt bush (Kalanchoe beharensis) from Madagascar, can grow into a small tree several meters tall, but most kalanchoes stay under 1 meter (3 feet).
Kalanchoe flowers have an interesting trick. Their petals open when the cells on the inner side grow faster, pushing the petals outward. To close, the cells on the outer side grow instead, pulling them back in.
Some kalanchoes, such as mother of thousands, grow tiny baby plants along the edges of their leaves. These drop off, take root, and grow into new plants – which is why they can spread quickly.
Growing Kalanchoe at Home
Light
Kalanchoes love bright light. Indoors, a sunny window is ideal – in the Northern Hemisphere, a south- or west-facing window in winter works well. Outdoors, give them morning sun and some shade during the hottest part of the afternoon, because strong midday sun can scorch the leaves. Plants that get plenty of light often develop attractive reddish edges on their leaves.
Planting and Pots
Photo by: Das Nili
Plant kalanchoes in a pot with drainage holes, using a fast-draining potting mix such as cactus and succulent mix. They like being a little snug, so choose a pot only slightly larger than the root ball. Repot every year or two into fresh soil, usually in spring after flowering.
Flaming Katy grows slowly and usually reaches about 15-45 cm (6-18 in) tall. As the plant ages, its stems can become woody. If it gets leggy, you can trim it back and root the cuttings in dry soil to make new plants.
Watering
Too much water is the most common way to kill a kalanchoe. Water thoroughly, then let the top of the soil dry out before watering again. In spring and summer, this might be about once a week; in winter, water much less. Never let the pot sit in a saucer of water, as soggy soil causes root rot.
Flowering
Kalanchoe flowers come in red, orange, yellow, pink, and white. In nature, flaming Katy blooms in late winter and spring. It is a short-day plant, which means it forms flower buds when nights are long. Plant growers control the light so they can sell flowering plants all year round.
Getting It to Bloom Again
Many people throw kalanchoes away after they finish flowering, but you can keep them going. Snip off the faded flower stalks and keep caring for the plant. To make it bloom again, give it about 14 hours of complete darkness every night for around six weeks – for example, by moving it into a closet each evening or covering it with a box – and water it a little less during this time. Once buds appear, return it to its normal spot.
Kalanchoe as a Gift Plant
Photo by: KENPEI
Kalanchoes are popular gifts because their bright flowers last for weeks. When the blooms start to fade, cut off the flower stems and let the plant rest, watering less until new growth appears. With good care, the same plant can flower year after year.
Safety tip: Kalanchoes are toxic to cats, dogs, and other pets if they chew the leaves or flowers. Keep them out of reach of pets and small children, and contact a vet if you think your pet has eaten some.
Kalanchoe FAQs
Where does kalanchoe come from?
Kalanchoes come from the Old World: Africa, Madagascar and Asia. Madagascar and eastern and southern Africa have the most kinds.
How tall does kalanchoe grow?
Most kalanchoes are about 15 to 45 centimetres tall when grown at home. The tallest, Kalanchoe beharensis from Madagascar, can reach about 6 metres.
What colour are kalanchoe flowers?
Kalanchoe flowers can be yellow, red, white or pink. They naturally bloom in spring.
Should you throw away a kalanchoe after it flowers?
No. Cut off the faded flower heads, give it less water and keep the plant in a place that is a little darker. It will keep growing.
How much sun does kalanchoe need?
Kalanchoes like bright light, especially in summer, but their water-filled leaves can be burned by strong direct sun. Morning sun with shade at noon works well.
Randi Jones is the owner and founder of the Nature Gift Store, an online retailer specializing in nature-themed gifts, educational science projects, live animal nature kits and real butterfly artwork. A biology graduate who fell in love with insects, she founded the company in 2001 to make active learning about nature fun, accessible and engaging for children and adults. Her store offers real butterfly frames, home and garden decor and educational live animal kits, including ant farms, worm farms, tadpoles, ladybugs and hermit crabs, and she runs a bug museum in Washington featuring live animals like Eddie the Iguana alongside other reptiles and insects.
