Q: Do I need to dig up my caladiums every year to keep them alive?
A: Caladiums need high organic, acid soils with consistent moisture but not too wet or soggy. Most of them do not like temperatures lower than the mid sixties. Therefore, it might work best to dig them up from the soil if you plan to keep them in the same site from year to year. Any diseased or damaged tubers should be destroyed. Healthy tubers should be cleaned of soil, dried and placed in a well ventilated area where temperatures will remain between 70°F and 90°F. Under these conditions, the tubers may sprout new leaves but they should not be planted outside until the outdoor soil temperature remains consistently above 65°F.
Some gardeners in Northeast Florida treat caladiums as annuals and replace them from year to year. Other gardeners have been successful at leaving the tubers in the ground but covering them with mulch to keep them warm during cooler times. Those living along the coast of Florida may have good success leaving caladiums in the ground under certain conditions such as protected, shady sites. If you really love the variety caladiums can give you, consider growing them in containers. This will make it easier to bring them inside from the cold during winter months. http://nassau.ifas.ufl.edu/horticulture/gardentalk/pdf/ufces-1060.pdf
Plant types range from the large fancy-leaf types to the short strap-leaf types. Some fancy-leaf types are sold as dwarf cultivars since they are much shorter plants but have broad leaves. By choosing the right cultivar and container size or shape, many combinations and effects can be achieved. There are cultivars with the ability to be grown in full sun; for example, fancy -leaved cultivars ‘Aaron’, ‘Candidum Junior.’, ‘Carolyn Whorton’, ‘Florida Elise’, ‘Florida Fantasy’, ‘Pink Cloud’, ‘Red Flash’. The strap-leaved cultivars ‘Florida Red Ruffles’, ‘Florida Irish Lace’, ‘Florida White Ruffles’, and ‘Florida Sweetheart’ and ‘Pink Gem’.
For more information on growing caladiums in Florida check out the brochure by the UF/IFAS Gulf Coast Research Center: http://caladiums.ifas.ufl.edu/CaladiumsBrochure.pdf