Gardeners' Dirt: Caladiums - options galore
By Beth Ellis - Victoria County Master GardenerEdited by Charla Borchers Leon
May 30, 2013 at 12:30 a.m.
As heat-loving tropicals, caladiums love our summers; however, our winters can sometimes be a bit chilly for them. If left in the ground to over-winter, they may come back - or not.
Victoria area homeowners, therefore, have three options when planting in spring: treat caladiums as summer loving annuals, lift the corms in fall and store until the following spring or leave them in the ground to overwinter, taking the gamble they'll come back when the weather warms up.
Gardeners can choose to buy caladiums as either plants or corms. If planting large beds, corms are most economical. They are graded by diameter and are available in different sizes, such as mammoth (ca. 4 inches), jumbo (ca. 3 inches), No. 1 (ca. 2 inches) and No. 2 (ca. 1 inch), as well as other sizes both larger and smaller.
Corm size to pot size
Be aware that corm size correlates to pot size. As per Evans, Harbaugh and Wilfret (1993), plant one mammoth corm per six inch pot; one jumbo corm per 5-inch pot; one No. 1 corm per 3 1/2 to 4-inch pot; and one No. 2 corm per cell of a six pack. Planting corms in pots that are too large increases the time it takes for plants to reach full growth.
Varying inches apart in ground
If planting directly in the ground where larger plants are desired, space big corms approximately 1 foot apart. If a border of shorter plants is desired, use smaller sized corms and space them about 6 inches apart.
If differences in plant height and density are important, try mixing fancy leaf and lance leaf caladiums, in addition to choosing appropriate corm sizes.
As noted in a previous article on caladiums published two weeks ago, fancy leaf caladiums (caladium bicolor hybrids) have a fewer number of large leaves on tall plants. Lance or strap leaf caladiums (caladium picturatum hybrids) have more leaves, but they are smaller and the plant is shorter. They also tend to be a little more cold and sun tolerant than fancy leaf caladiums.
Lifting corms each fall
Many gardeners choose to lift and store corms in fall. To do so, dig up the corms and allow foliage to wither away. Wash, thoroughly dry and treat corms with fungicide. Store at around 70 degrees in paper bags with dry peat moss or dry sand. Once corms resprout, plant them in appropriately sized containers and keep them inside until it gets warm enough to transfer the plants back out into the garden.
Caladiums overwintered in the ground need protection from cold snaps. If the top few inches of soil falls below 65 degrees for extended periods, corms are in danger of being cold damaged or killed.
To provide protection, apply a thick layer of mulch. Cover the area with blankets if cold temperatures threaten. While cold-damaged corms may resprout in spring, the plants will likely have lost hardiness.
There's a trick gardeners use to increase the number of leaves a fancy leaf caladium will produce. It's called "de-eying" and involves removing the dominant bud, or eye, from the corm.
Fancy leaf caladiums that have not been de-eyed put most of their energy into dominant buds, producing taller plants with fewer but larger leaves. De-eying causes corms to rely on multiple secondary buds to produce leaves. This results in more leaves on a shorter, fuller plant.
For an excellent tutorial on de-eying, visit classiccaladiumsllc.com/de-eye_caladiums.htm. De-eying is generally not needed for lance leaf caladiums, since they are already compact growers.
Caladiums in pots
Both fancy and lance leaf caladiums can be grown in containers. Lance leaf varieties do well in hanging baskets, densely planted in standard flower pots and as understory companions to taller plants.
Fancy leaf caladiums usually do best in non-hanging pots given their height and leaf size. Use them in three ways - grown as single plants, contrasting the verticality of the long stems against the large, colorful, nodding leaves; in companion plantings emphasizing variations in height, texture and color; and in large, homogenous groups to create bold uniform statements.
Go forth, plant
Tall plants or short, many leaves or few, subtly or brilliantly colored, caladiums provide the gardener with many options. Treat them as annuals. Leave them in the ground or lift the corms in fall and try your hand at overwintering.
Mix fancy with lance leaf varieties, choosing contrasting colors to play up differences. Experiment with corm sizes or give de-eying a try.
Regardless of what you decide, caladiums will make that otherwise dark spot on your property absolutely glow.
The Gardeners' Dirt is written by members of the Victoria County Master Gardener Association, an educational outreach of Texas AgriLife Extension - Victoria County. Mail your questions in care of the Advocate, P.O. Box 1518, Victoria, TX 77901; or firstname.lastname@example.org, or comment on this column at VictoriaAdvocate.com.