Common pests and plant diseases Caladiums are relatively pest and disease free but susceptible to caterpillars and aphids. Maintaining a healthy soil, sun and water balance helps prevent infestations. If you notice marks or holes in the foliage, treat them with insecticidal soap. This treatment should also help avoid mealybugs, mites, thrips and whiteflies. If there are only a few pests, try to remove them by hand. Deer and rabbits occasionally graze on caladiums.
Some diseases that affect caladium include fungal pathogens that infect the tubers, such as Rhizoctonia and Pythium species. Fungal infections like these, and blight, infect the soil and destroy the tuber.
