Kalanchoe

How to care for Kalanchoe

Light

Kalanchoe blossfeldiana performs best in bright, indirect light, such as a position near a south- or east-facing window where it receives a few hours of gentle sun each day. Too little light results in weak, leggy growth and poor flowering, while harsh afternoon sun through glass can scorch the fleshy leaves. When days lengthen in summer, move the plant away from direct midday sun. To encourage re-flowering, the plant must receive 14 or more hours of uninterrupted darkness each night for at least six consecutive weeks; even brief exposure to artificial light during this period will interrupt the process.

Watering

As a succulent, Kalanchoe blossfeldiana is susceptible to root rot if overwatered. Water thoroughly when the top half of the compost has dried out, then allow excess water to drain freely from the pot. Empty saucers after 30 minutes to prevent the roots from sitting in standing water. Reduce watering further in winter when growth slows. Always water at the base of the plant rather than over the foliage or flowers, and use room-temperature water if possible.

Soil and potting

A free-draining compost is essential. A proprietary cactus and succulent compost is ideal, or a standard peat-free houseplant compost mixed with approximately one third horticultural grit or perlite. Good drainage prevents waterlogging, which is the most common cause of plant failure. Ensure the pot has adequate drainage holes.

Feeding

Feed with a balanced liquid fertiliser at half the recommended strength once a month during spring and summer. Switch to a low-nitrogen, higher-potassium feed (such as a tomato fertiliser) in the weeks leading up to the desired flowering period to encourage bud development. Do not feed during the short-day conditioning period or in the depths of winter when the plant is resting.

Humidity and temperature

Kalanchoe blossfeldiana tolerates the relatively dry air typical of centrally heated homes and does not require misting. It prefers temperatures between 15 and 29 degrees C during the growing season and should be kept above 10 degrees C at all times. Avoid positioning the plant near cold draughts, open windows in winter, or directly above radiators, as both extremes cause stress and can lead to premature leaf or flower drop.

Repotting

Repot every one to two years in spring, moving the plant into a pot only one size larger. Kalanchoe blossfeldiana grows well when slightly root-bound, so there is little benefit in potting into excessively large containers. Use fresh succulent compost at each repotting. If the plant becomes very large or straggly after several years, it is often easier to propagate fresh cuttings than to continue repotting the parent plant.

Pruning

Deadhead spent flower clusters promptly by cutting the stem back to the next set of leaves, which keeps the plant tidy and may extend the overall flowering period. Once all flowering has finished, cut leggy stems back by about one third to encourage a more compact, bushy habit. Regularly pinching out the growing tips of young plants promotes branching. Remove any yellowing or dead leaves at the base of the plant to improve air circulation and reduce the risk of fungal disease.

Is Kalanchoe toxic?

Common problems

How to propagate

Stem cuttings

Take a healthy stem cutting of 5 to 8 cm in late spring or early summer, remove the lower leaves, and allow the cut end to callous over for 24 hours. Insert into barely moist succulent compost and place in bright, indirect light; roots should form within two to four weeks.

Leaf cuttings

Remove a healthy, intact leaf from the parent plant and allow the base to dry for a day. Lay the leaf on the surface of moist succulent compost or insert the base shallowly; small plantlets will eventually develop at the base of the leaf, though this method is slower and less reliable than stem cuttings.

Seed

Sow fresh seed on the surface of moist seed compost in spring, as the seeds require light to germinate. Cover with a propagator lid or clear film and maintain a temperature of around 21 degrees C; germination typically occurs within two to three weeks, though seedlings take considerably longer to reach flowering size than vegetatively propagated plants.

Where Kalanchoe comes from

Native to Madagascar.

Story and origins

The genus name Kalanchoe is derived from the Chinese words 'Kalan Chauhuy', meaning 'that which falls and grows', a reference to the way plantlets of some species in the genus drop from the leaf margins and root where they land. This characteristic is particularly pronounced in related species such as Kalanchoe daigremontiana. The species epithet blossfeldiana honours Robert Blossfeld, a German plant collector and nurseryman who collected specimens in Madagascar in the early twentieth century and subsequently introduced the plant to cultivation in Europe.

Kalanchoe blossfeldiana was first collected in Madagascar by Robert Blossfeld during an expedition in the 1920s and was formally described and introduced to the European horticultural trade in 1932. It was quickly recognised as a commercially valuable flowering houseplant owing to its long blooming period, compact habit, and ease of cultivation. By the latter half of the twentieth century, large-scale commercial production had been established across the Netherlands, Denmark, and Germany, and controlled-environment growing had made it available in flower throughout the year. In many European countries, including the United Kingdom, it became a standard gift plant associated with Christmas and the New Year, though its availability is now entirely seasonal-agnostic. In its native Madagascar the plant grows on rocky slopes and cliff faces, where the free-draining habitat mirrors the well-drained conditions it requires in cultivation.

Varieties to know

Kalanchoe blossfeldiana 'Calandiva'

A very popular series with fully double, rose-like flowers; longer-lasting blooms than the single-flowered types and available in a wide colour range.

Kalanchoe blossfeldiana 'Kerinci'

Features unusual bi-coloured flowers with contrasting edges; part of a group bred for distinctive patterned petals.

Kalanchoe blossfeldiana 'Simone'

A compact cultivar with vivid pink double flowers, suited to small pots and windowsill growing.

Kalanchoe blossfeldiana 'Gold Strike'

Notable for its bright golden-yellow single flowers, one of the cleaner yellow selections in commercial production.

Kalanchoe blossfeldiana 'Tenorio'

A series bred for tall, upright growth and large flower clusters in deep red and orange shades, popular as a cut-flower subject.

Fun facts

• Kalanchoe blossfeldiana was introduced to European horticulture in 1932 by the German nurseryman Robert Blossfeld, after whom the species epithet is named.
• Commercial growers use artificial blackout systems to manipulate the plant's day length, enabling them to produce flowering specimens at any time of year regardless of season.
• The bufadienolide compounds found in Kalanchoe species are structurally related to the cardiac glycosides in Digitalis (foxglove) and have been studied for potential pharmaceutical properties.
• Despite being native to tropical Madagascar, Kalanchoe blossfeldiana has proved highly adaptable to the conditions of temperate interiors and is consistently one of the best-selling flowering houseplants in the United Kingdom.
• A single plant can produce hundreds of individual flowers during a blooming period, which typically lasts six to eight weeks under good conditions.

Kalanchoe FAQ