Any garden with a shady location has a perfect spot for caladiums. These tropical tubers, most of them varieties derived from Caladium bicolor, are grown for their dramatic summer foliage. They are naturals in beds with ferns or coleus, in pots to accent shady spots, or used as indoor houseplants.
Special features of caladiums
Caladium bicolor is widely available at garden centers and nurseries. The leaf shape is oval or like an arrowhead. There are a multiple hybrids available offering a range of leaf colors and patterns.
Tall varieties such as white 'Candidum' and pink 'Carolyn Whorton' put on a beautiful show, but since each tuber has only one to three active buds, the leaf count is low.
Lance-leaved types, including 'Rosalie' and 'White Wing', produce many more leaves from multiple buds, but the leaves are thinner and not as long.
Choosing a site to grow caladiums
Select a shady area that is moist, well drained, humus rich, and slightly acidic. Caladiums are popular grown around the bases of trees, but for this planting scheme to work, you will need to create a 5-inch-deep bed of rich soil so the tuberous roots will have adequate space and a fair chance at moisture.
In the warm, humid climates of zones 8 and 9, plant caladium tubers directly into the ground in spring. In most other areas, you'll save several weeks of growing time by transplanting potted plants that are already up and growing.
To make watering and fertilizing easier, consider planting three tubers (or plants) in 6-inch pots and sink the pots up to their rims in the beds. The pots collect and hold water, stave off invasions from thirsty tree roots, and make it simple to lift and collect the tubers in fall.
Because caladiums are basically all leaves, they thrive on regular fertilizer. To keep plenty of new leaves coming on, feed with a balanced soluble fertilizer such as 10-10-10 twice a month.
The great advantage of pot-grown caladiums is that you can move them about as needed to keep them warm. When nights become chilly in fall, bring them indoors and keep in a sunny window, until the leaves begin to wither. At that point, let them dry out completely. To save space, you can collect the tubers, shake off the soil, and stash them in old hosiery or a mesh bag for up to five months. As long as the tubers are stored above 60d F, they will be ready to replant the following spring.