Caladium

How to care for Caladium

Light

Caladiums thrive in bright, indirect light. Direct sun will scorch the delicate leaves, causing bleached or brown patches. A position near an east or north-facing window, or set back from a south or west-facing one, works well. Varieties with more white or pink in the leaves tend to need slightly more light than predominantly green ones, which can tolerate dimmer conditions without losing vibrancy.

Watering

During active growth, water consistently to keep the compost evenly moist but never waterlogged, as tubers are prone to rotting in saturated soil. Allow the top centimetre of compost to dry slightly between waterings. As the leaves begin to die back in late summer or autumn, gradually reduce watering until the compost is almost dry. During dormancy, water only enough to prevent the tuber from completely shrivelling.

Soil and potting

Use a light, well-draining potting mix that retains some moisture without becoming compacted or waterlogged. A peat-free multipurpose compost blended with perlite at a ratio of roughly 2:1 is suitable. Good drainage is essential to prevent tuber rot. Slightly acidic to neutral pH, in the range of 5.5 to 6.5, is preferred.

Feeding

Feed with a balanced, water-soluble fertiliser every two to four weeks from the time new growth emerges in spring through to late summer. Avoid high-nitrogen feeds, which encourage leafy growth at the expense of colour intensity. Cease feeding entirely once the plant begins to enter dormancy and resume only when new shoots appear the following season.

Humidity and temperature

Caladiums require high humidity, ideally above 60%, to perform well indoors. Low humidity causes leaf edges to brown and curl. Misting, grouping plants together, or placing pots on a pebble tray filled with water are effective ways to raise ambient humidity. Maintain temperatures between 18 and 29 C during the growing season. Cold draughts and temperatures below 15 C will cause the leaves to collapse, and tubers stored below this threshold are liable to rot or fail to reshoot.

Repotting

Repot tubers each spring at the start of the growing season, or when starting tubers into growth after dormancy. Choose a pot only slightly larger than the tuber, as excessively large pots hold too much moisture and increase the risk of rot. Plant tubers with the knobbly side facing upwards, approximately 2.5 cm below the soil surface. Terracotta pots are helpful as they allow excess moisture to evaporate through the sides.

Pruning

Pruning is minimal. Remove individual leaves as they yellow or become damaged to keep the plant tidy and redirect energy. Do not remove leaves that are still green and functioning. As dormancy approaches, allow the foliage to die back naturally rather than cutting it prematurely, so the tuber can reabsorb nutrients from the dying leaves. Dead foliage can then be removed cleanly at soil level.

Is Caladium toxic?

Common problems

How to propagate

Tuber division

At the start of the growing season, lift the dormant tuber and use a clean, sharp knife to divide it into sections, ensuring each piece has at least one growing bud or eye. Dust the cut surfaces with sulphur or cinnamon to prevent infection, allow them to callous for a few hours, then pot each section into moist compost and keep warm.

Offsets

Mature tubers often produce small offset tubers around their base. These can be gently detached at repotting time in spring and potted individually into suitable compost. Keep them warm and moist and they will typically sprout within a few weeks.

Where Caladium comes from

Native to Argentina Northwest, Bolivia, Brazil North, Brazil Northeast, Brazil South, Brazil Southeast, Brazil West-Central, Colombia, Costa Rica, Ecuador, French Guiana, Guyana, Honduras, Nicaragua, Panamá, Peru, Suriname, Venezuela. Now naturalised or cultivated in 35 other regions worldwide.

Story and origins

The genus name Caladium is derived from the Malay word 'keladi', a term applied broadly to plants in the arum family that produce edible or ornamental corms and tubers. It was adopted into botanical Latin by the botanist Heinrich Wilhelm Schott in the nineteenth century. The species epithet bicolor means 'two-coloured' in Latin, a reference to the contrasting colours typically seen on the leaves, though in practice cultivated forms display far more than two colours.

Caladium bicolor was first described to European science following the botanical exploration of tropical South America in the eighteenth century. Plants were being cultivated in European glasshouses by the 1770s, and by the mid-nineteenth century caladiums had become enormously fashionable among wealthy collectors, who commissioned specialist growers to produce ever more elaborate colour patterns. Belgian and French nurseries were particularly prominent in developing new varieties during this period. In their native range in Brazil and surrounding countries, various caladium species have long been used in traditional medicine, though internal use is hazardous given their toxicity. The genus also carries symbolic associations in some South American cultures, where the vivid foliage is connected with celebration and decoration.

Varieties to know

Caladium bicolor 'White Queen'

Predominantly white leaves with red veining and green margins; one of the classic cultivars for indoor use.

Caladium bicolor 'Florida Sweetheart'

Compact habit with pink and white leaves edged in green; well suited to containers and lower light conditions.

Caladium bicolor 'Red Flash'

Bold red leaves with contrasting green edges and pink spots; a vigorous grower tolerating relatively bright conditions.

Caladium bicolor 'Candidum'

White leaves with vivid green veining; one of the oldest and most widely recognised cultivars in cultivation.

Caladium bicolor 'Rosebud'

Deep rose-pink centre fading to white and green margins; appreciated for its unusually deep colouration.

Fun facts

• Caladium bicolor has been cultivated in Europe since at least the mid-eighteenth century and was among the most fashionable foliage plants of the Victorian era, with breeders producing hundreds of named cultivars.
• The translucent quality of caladium leaves allows light to pass through the blade, an adaptation thought to improve photosynthetic efficiency on the dimly lit tropical forest floor.
• Florida, USA, produces the vast majority of caladium tubers sold worldwide commercially, with the industry centred around Lake Placid, which calls itself the Caladium Capital of the World.
• The calcium oxalate crystals that make caladiums toxic act as a mechanical defence against herbivores; the needle-like raphides cause immediate pain and deter further feeding.
• Despite being described as Caladium bicolor, the species encompasses an enormous range of leaf colour patterns, and most commercially sold caladiums are complex hybrids rather than the true wild species.

Caladium FAQ