The All-Season Color of Caladiums

In the past few years, foliage plants have become quite popular.  There is a renewed interest in the beauty of different textures, shapes, and colors of leaves that when combined create a unique visual display indoors or out. 

There are none more unique and outstanding than Caladiums.

Caladiums are beautiful, colorful foliage plants that are native to South American tropical forests.  There are over 1000 cultivars of Caladium; each with its own unique leaf color and pattern.  Depending on the variety, some of the leaves are huge, while others produce smaller but equally colorful, patterned foliage.   

Caladiums are actually tubers that create leaves from spring to fall.  They can be grown indoors or out in spring and summer.   In our climate, they are usually grown in pots as while they can go outside in spring and summer, they cannot tolerate our fall frosts and winters.  When fall approaches they begin to transition into a dormancy rest period for about 5 months and will produce new growth in spring.   During the rest period they should be brought into the house before the first fall frosts occur. 

There are two main leaf types; fancy and strap-leaf.  The fancy varieties have heart-shaped leaves and the strap-leaf have narrower arrow shaped foliage. They all like warmth and humidity.

Most caladium varieties like a part-sun to shady location outdoors. The newer thick- leaf varieties can tolerate bright light.   If you are growing them indoors locate them in a bright room but no direct sun.  Too much sun scorches the leaves.  A north or east window exposure is best away from drafty doors or windows.  Extra humidity in the house is required.  The easiest way to raise the humidity around the plant is to place it on a tray of pebbles.  Keep this tray filled with water but never let the pot sit directly in the pebbles. 

Ideally caladiums need to be in planted in spring in a rich, somewhat peat moss based acidic soil.  The container should have excellent drainage.  Each tuber has a large central bud.  To encourage bushiness, lift out the large central bud with the tip of a sharp knife.    This will result in a bushier plant.

Tubers should be planted 2.5 to 5 cm. deep with the eye buds facing up.  Water well.  Do not water again until you see bud/ leaf growth or the soil becomes very dry.  You want to avoid root rot at all costs as this can lead to plant death. 

As your caladium matures, water weekly.  Fertilize in spring and summer once every two weeks with a ¼ strength all- purpose water- soluble fertilizer such as 20-20-20.

As late fall approaches, you will notice the leaves beginning to yellow and eventually fall over.  You have two options:

1. After the foliage has totally yellowed and fallen over, lift the tuber, brush off the soil and leave in a warm, dry location for 10 days to dry out.  Disinfect your cutting tool with alcohol and cut off the foliage, dust the tuber with a fungicide to prevent infection and place in a breathable bag or in a box and cover with dry peat moss/vermiculite.
2. While the foliage is yellowing, withhold water and wait for the leaves to fall over. Cut off the leaves at soil level, leaving the tuber in the pot. 

Whatever method you choose, store your tubers in a dark and dry location, no cooler than 18 degrees Celsius.  Do not water during the rest period. 

Repot your tubers into new soil in the spring.  This is also the time to divide large tubers and let them dry for a couple of days before dusting with fungicide (bulb dust) and planting into the new soil. 

Water well and reintroduce them to bright light in the house or outside in part shade after the last spring frost.

Please note:

Caladiums are toxic if ingested and may irritate the skin.   They are especially toxic to cats and dogs.

Caladiums rarely flower.