Richard C. Bogren, Gill, Daniel J.
By Dan Gill
LSU AgCenter Horticulturist
(05/04/18) If you asked me what some of my favorite plants for summer color are, caladiums would absolutely be on the list. You won’t find a better plant for reliable color in areas that get some shade. And one investment can provide years of color.
Easy enough for the casual gardener to expect routine success, the caladium’s elegant beauty also makes it a staple in the most accomplished gardener’s landscape. Native to tropical South America, caladiums grow from tubers and thrive in the heat and humidity of our long summers. They are remarkably free of major insect or disease problems.
Caladiums (Caladium x hortulanum) are grown for their attractive foliage. The 6-to-12-inch heart-shaped leaves emerge from the ground on arching stems that are generally 1 to 2 feet tall but can grow taller. The foliage may be splashed with combinations of white, pink, rose, red, burgundy, chartreuse or green, often with several colors combining in wonderful patterns. These bright leaves with their bold texture embellish our shady gardens from May until October when the tubers go dormant.
Where to plant
Caladiums grow best in shade to part shade (two to four hours of direct sun, preferably morning) or bright dappled light. In these conditions, they produce the lushest growth with large, colorful leaves. The caladium plants you purchase at nurseries are usually grown in shady greenhouses, and the foliage will often scorch or burn if you plant them into beds that receive too much direct sun. This often results in brown areas and holes literally burned into the leaves. If the light conditions are appropriate, the new leaves that emerge will be adapted to the increased light and not burn.
Some cultivars are more tolerant of sunny conditions and are successful in beds receiving part to full sun (six hours or more of direct sun) as long as they receive adequate irrigation. When grown in full sun, caladiums tend to produce smaller and more brightly colored foliage, and the plants will be shorter.
The following caladium cultivars are recommended for full sun based on research done at the LSU AgCenter Hammond Research Station: Fire Chief (fancy-leaf red), Hearts Delight (lance-leaf red), Carolyn Whorton (fancy-leaf pink), Cherry Tart (lance-leaf red), Moonlight (fancy-leaf white), Florida Sweetheart (lance-leaf pink), White Cap (fancy-leaf white and green), White Ruffles (lance-leaf white), Celebration (fancy-leaf multi-color) and White Dynasty (lance-leaf white). Fancy-leaf caladiums have larger, heart-shaped leaves. Lance-leaf caladiums have smaller, narrower spearhead-shaped leaves. These cultivars also do well in the shade.
You can purchase caladiums two different ways. Buying caladium tubers is the most economical way to add caladiums to your landscape. You can buy caladium tubers and plant them directly into well-prepared beds now. Plant the tubers about 2 inches deep and 8 to 12 inches apart.
You should see growing points or even pinkish-white sprouts on the knobby side of the tuber. That side is planted up. The smoother side is the bottom of the tuber. Wait until unsprouted tubers have emerged and grown several inches tall before mulching them.
Caladiums are also available growing in 4- to 6-inch pots, and they will provide immediate color in the landscape. Growing caladium bulbs should be planted with the top of the root ball level with the soil of the bed. Plant them 8 to 12 inches apart into well-prepared beds, and they will grow larger and more beautiful through the summer. Once growing caladiums are planted, mulch the bed with 2 inches of your favorite mulch and water them in. Keep beds of caladiums well-watered during the summer, especially those receiving lots of sun.
In late September or early October, longer nights and cooler temperatures encourage caladiums to go dormant. But the tubers you plant this summer can be used to grow caladiums next year, either left in the ground or stored and replanted. If the beds where the caladiums are planted will stay relatively undisturbed and if drainage is good and they will not stay too wet during winter, you may simply leave the caladium tubers in the ground.
Or you may choose to dig and store them. This is the most reliable way of making sure they grow another year. Dig caladiums when a number of leaves turn yellow and most of the foliage begins to look “tired” and falls over. Use a shovel or a garden fork to lift the tubers, being careful not to damage them. Leaving the foliage attached, shake and brush off most of the soil from the tubers and lay them out in a single layer in a dry location sheltered from rain (in a garage, under a carport). After the foliage becomes tan and papery in appearance, pull it from the tubers and store the tubers in paper bags indoors where temperatures stay around 70 degrees through winter.
With poor growing conditions, particularly in areas of heavy shade or sunny, dry locations, the plants will likely produce small, weak tubers that may not return well either left in the ground or dug and stored. Under the right circumstances and with proper care, however, the tubers you plant this year can provide a beautiful display again next year and for years to come.
This Carolyn Wharton caladium does well in a pot on a patio. Photo by Dan Gill/LSU AgCenter
Scarlet Flame is a lance-leaf caladium with dark scarlet red patches on rose-red leaves circled with a dark green edge. Scarlet Flame can take more sun than traditional fancy leaf caladiums. Photo by Yan Chen/LSU AgCenter