Caladium are grown for the showy arrowhead shaped leaves which range from 6-18” (15-45cm) long and nearly as wide. Originally there were 15 species and over 1000 cultivars from Central and South Americas mainly in the jungles of Brazil and the Amazon. Most grow 24” tall (60cm) and 24” (60cm) wide but there are now dwarf cultivars. You will see every combination of white, green, pink and red in the simple to intricately painted leaves. Caladium candidum, ‘angels wings’, is a delicately beautiful foliage plant with its large translucent white leaves and heavy green veins. Caladium is a wonderful houseplant for a plant lover with little or no outdoor space as you can enjoy it during its growing period and swap it out for another in its place while it rests.
Light and Temperature
Caladium love lots of light and heat. They are tropical and do not tolerate the cold (air conditioning) or drafts. Most varieties can never be in direct sun as their skin is too thin and will burn but love the light nonetheless. Full to partial shade is preferred for all. The thicker the leaf the more sun it can tolerate. The hotter the temperature the faster they will grow. As an indoor potted plant the Caladium needs a lot of light. It will reach for the light and can become leggy. A lot of indoor plants do not like to be moved but the Caladium does well if turned, a quarter turn, perhaps every Sunday. Depending on the number of sunny days in your location you could, for instance, in Michigan put your Caladium in a filtered southern facing window as Michigan has, on average, 65-75 days of sun per year opposed to Arizona where you should put your Caladium in a northern facing window as there is an average of 160-240 days of full sun. A southern exposure filtered or not in Arizona, would burn the leaves. If you have a very bright bathroom or can put a good grow light in your bathroom your Caladium will thrive. The more humid the area the more easily your plant can change sunlight into the energy it needs.
Found in open areas under the forest canopy or along the banks of rivers you need to keep the soil of your Caladium evenly moist but not soggy from early spring through the summer. Do not let the pot sit in water. Being a heat loving tropical plant with leaves that are quite thin they also require high humidity, especially while the new leaves are forming.
Outdoors or as a houseplant, the Caladium one of the few deciduous foliage plants dying back to the soil each fall. Even with the best conditions your plant will display its colorful foliage only 6-8 months before you begin to see the foliage begin to die back. This is a normal rest period but until then there will be a colorful show. Beginning in the fall when the foliage takes on a tired appearance you will cut back gradually on the watering, until the leaves shrivel up and fall. Remove the tubers from the pot at this time (described below) or just keep the pot in a warm area, 60-65°F (15.5-18.3°C), through the winter months, with no water until early spring when the soil should get its first watering and the plant moved into a 75°F (24°C) temperature.
Caladium like a humusy (leaf mold) rich in organic matter but well drained soil. A mix containing 1 part aged compost from leaf mold, 1 part loam or humus, and 2 parts coarse sand, perlite or pumice would be a nice combination for this plant. The compost and humus will help retain moisture and provide nutrients and the sand will provide the aeration necessary.
Every week, from spring through July, you can use a water soluble 6/6/6 fertilizer to promote strong foliage growth. If you have repotted your tubers into fresh organically rich medium you can wait for the new growth to reach 2-3” (5.8-7.62cm) before feeding as there will be enough nutrients in the dirt to get it going.
You may see what look like seedpods. This is the flower and if you don’t like its looks or if you want the plant to focus energy for leaf production you can remove it by cutting it off at the soil level.
Pests and Problems
You may see dark spots on the lower leaves. They are diseased and you should remove and destroy them. Do not put them into any compost you will be using either indoors or outside. You may see burning on the edges of the leaves. This can be caused from fertilizer touching the roots or not enough water. Leaves curling under and brown or deformed leaves and leaf tips can be a sign of too little humidity.
Most pests will leave a Caladium alone but you may notice leaves curling,twisting or appearing stunted. This may be evidence of aphids, Mealybugs can also be attracted to Caladium. The leaves appear stunted and you may notice a sticky trail of honeydew on the leaves. Thrips and whiteflies may also be a problem. Spider mites could also be a pest on this plant. There are easy ways to combat these pests so be sure to periodically inspect the leaves for any infestation so you can control things early. One bonus is that this is a seasonal plant indoors and any pest issues will not kill the plant. It will naturally die back in the late fall and the pests will be gone by spring when the new shoots emerge from the underground tubers.
Caladium are grown from tubers. If the tubers get too cold or too wet they can become soft or rot. When the leaves go dormant you can leave them in the pot and keep it warm and dry or you can lift the tubers out, clean the pot, trim the leaves back to the bulb and store above 60-65°F (15.5-18.3°C) in a mesh bag of sawdust or a cardboard box of peat moss with good ventilation. You should check the tubers periodically for softness or rot and discard any that you think may not grow your desired show the next spring. You can then replant in early spring, separating the tubers into several pots if getting too crowded. Plant in fresh medium or begin the watering schedule if you’ve left your Caladium in the pot through the rest period. To divide a Caladium that has overwintered in its pot you should wait for several inches if new growth before detaching small tubers from the parent plant and repotting.
A humid greenhouse with ample shade and 75F (24C) degrees is ideal for Caladium should you be so lucky.
Should you happen to purchase tubers, the larger the tuber the larger the leaf will be and you plant them 1-2” (2.5-5 cm) deep with the sprouts facing upward.