Caladiums for Home Gardeners and Hobbyists

Not only can caladiums be enjoyed as houseplants (potted plant), on the patio (potted plant or in combination planters) and in the landscape (depending on variety as border, intermediate or background plantings) but also caladium leaves can be cut to make beautiful and unique arrangements either alone or in combination with cut flowers.  Caladium leaves last 2 weeks or more. Caladium pot and combination planters can be purchased from large chain stores and from garden centers and nurseries in the spring.  Bulbs usually can be purchased during this time as well.  Featuring the latest releases as well as the “Classics”, bulbs are available on line from Classic Caladiums from March 1 through the end of June.  « Red Flash Caladiums in a rain barrel

Bulbs should be planted in the landscape in the spring after the last frost.  The USDA temperature zone chart provides the following guidelines, however temperatures can vary in specific locales therefore nothing substitutes for local knowledge for exact planting dates:

• Zones 10 April 1

• Zones 8-9 May 1

• Zones 6-7 June 1

• Zones 3-5 July 1

Caladium bulbs are sold in various size grades based on the diameter of the bulb.  The bulbs are categorized into the following traditional sizes:

• No. 2:  1” to 1 ½” (2.5 – 4.0 cm)

• No. 1:  1 ½” to 2 ½” (4.0 – 6.5 cm)

• Jumbo:  2 ½” to 3 ½” (6.5 – 9.0 cm)

• Mammoth:  3 ½” to 4 ½” (9.0 – 11.5 cm)

Generally the larger the bulb you purchase the better the performance as the bulb it the source of energy reserve for the plant, therefore the larger the bulb the larger the energy reserve thus the opportunity for better performance.

Bulbs should be planted in cultivated soil.  The higher the organic matter content of the soil the better.  Bulbs should be planted right side up and covered with 2”-3” of soil.  Caladiums are aggressive feeders.  Environmentally responsible feeding would include the use of a balanced (10-10-10) 90-180 day (90 days in the north and 180 days in the south) controlled release fertilizer.  Caladiums are tropical plants originally from the rain forests of Latin America and therefore enjoy water.  In fact sun tolerance is associated with water availability.  Given adequate water, many caladium varieties not classified as full sun varieties in fact can tolerate full sun.  Caladiums are relative pest free, however sometimes worms can cause minor problems.  It is usually just best to pick them off.  Root Knot nematodes can be a problem in some areas - if this poses a problem simply rotate your plantings with other types of plants.

Where caladiums should be planted in the garden depends on the variety.  In general strap leaf varieties are more sun tolerant and shorter than most fancy leafed varieties, however there are plenty of exceptions.  This excel chart link provides guide lines as to growing time, sun tolerance and height and should be used in designing your plantings.

In general caladium bulbs do not over winter well in the soil.  As with any rule there are exceptions.  Being tropical caladiums will over winter in the soil in southern Florida (Zone 10).  They have been known to over winter in the southern parts of the Gulf States (Zone 9) when we have mild winters.  If you wish to preserve your bulbs it is best to dig them in the fall and store them in a paper bag in a warm dry area.  Do not allow them to be exposed to temperatures below 65°F.  Since caladium bulbs can accumulate pathogens the safest thing is to purchase new bulbs each spring from a professional bulb producer.