CALADIUMS
by Jerry Parsons, Ph.D.
Horticulture Specialist, Texas Agricultural Extension Service
in San Antonio
It's finally April and spring has sprung in
this area. But because this has been a mild winter and early
spring-like weather began in February, most people have the
mistaken idea that everything should have been planted. Wrong!
There is some planting which should be delayed until April.
Those better-late-than-early planted crops include okra, sweet
potatoes and the most beautiful of the non-flowering ornamentals,
the caladium.
Most people rushed out and purchased caladiums
as soon as bulbs were available. The selection was better!
Maybe the selection was better but how did you know which
varieties were best to select? Most people just look at the
picture on the display box. If you chose vegetable varieties
using that technique, you are setting yourself up for a real
disaster. The only way to insure that a variety is a winner
is to test it against others.
There is no caladium-testing program in this
area but the Dallas Botanical Center has been conducting tests
of about 100 varieties for nearly a decade. Results of their
extensive testing program should give us some idea of the
true winners in the caladium kingdom. Those of you who have
waited until now will reap the benefits of this information.
Those "early birds" will just have to wait until
next spring to get their "money's worth" from caladium
purchases.
Flamboyant foliage is the hallmark of these
remarkably versatile garden plants. Lush as the Amazon jungles
of their origin, caladiums can add unique tropical flair to
summer gardens anywhere in the country. The leaves attain
their fullest size and deepest colors when grown in 60 percent
shade ? ? spots where filtered or morning sun falls only 3
to 4 hours daily.
"Fancy Leaf" caladiums are the most
useful in home landscapes. Derived from Caladium bicolor,
a Brazilian species, the broad heart-shaped foliage usually
is a riot of pink, red, white and green splotches. Some varieties
are solid red or white with deep-green trim along veins and
outer edges. The pinkish flowers are short-lived, but leaves
remain fresh and vibrant all summer long.
Planted in naturalistic clusters, the one-foot-tall
foliage outshines traditional ground covers. Caladiums also
enliven shaded foundation plantings and shrub borders. Deep
shade is not advisable for caladiums, but full sun is fine
as long as soil is kept sufficiently moist.
"Lance Leaf" caladiums (derived from
Caladium picturantum) are smaller and more compact. Their
pretty, ruffle-edged foliage seems tailor-made for window
boxes and patio planters. These plants also thrive indoors
near bright windows.
Caladiums are closely related to the popular
and almost indestructible philodendron --and are just as resilient
despite their delicate appearance. In fact, few garden plants
are easier to grow.
Foliage sprouts from bulb-like tubers, which
are available during spring and early summer, as are caladium
seedlings and full-size plants. Gardeners have dozens of multi-colored
varieties to choose from. For economy --especially when mass
planting --go with tubers. Delay planting until all danger
of frost has passed and soil begins to warm. (That's now folks!)
Caladiums tolerate most soils but perform best in earth that
is richly organic. If soil is sandy or heavy with clay, spade
in peat moss or compost at planting time.
Place tubers bud side up in furrows or individual
holes 9 to 15 inches apart. Cover with 3 inches of soil, tamping
firmly around each tuber to eliminate air pockets. Water immediately.
Thereafter, moisten only when the soil surface becomes dry.
A 2 to 3-inch mulch of wood chips, ground bark or other organic
material helps retain soil moisture and discourages weeds.
Want to try something sadistic on your caladium
bulbs this year? Try cutting their eyes out! What a sick idea!
But it will result in more leaves and remember, leaves of
brightly colored foliage is what caladiums are all about.
Just take a sharp spoon or knife and scoop or cut off the
apparent eyes or buds on the tubers before planting. Such
a procedure delays emergence for a few days but it causes
the tuber to sprout more dormant buds rather than the fewer
main buds. The result is an abundance of foliage rather than
a few shoots. Try some and leave some -see which gives the
better results.
Depending on soil conditions, the first leaves
break soil 3 to 6 weeks after planting, setting shaded areas
aglow. Keep the caladiums glowing by applying fertilizer around
emerging plants. A good rule of thumb is 2 pounds of 19?5?9
per 100 square feet of planting bed. Re-apply monthly. As
plants fill out, a liquid fertilizer drench may be more convenient.
Standard houseplant food suffices for container-grown caladiums.
So which are the best caladium varieties? I
will list the variety name, the 4-year average survival period
(in weeks) and the 4-year average height (in inches).
The best of the standard, "fancy leaf"
types are Candidum (21) (19), Carolyn Whorton (23) (22), Fire
Chief (21) (20), Florida Beauty (22) (24), Galaxy (24) (21),
Miss Chicago (21) (20), Pink Shell (21) (15), White Christmas
(21) (19), White Queen (22) (21).
The best of the strap or "lance leaf"
types are Caloosahatchie (23) (14), Candidum Jr. (21) (14),
White Wing (22) (18), Pink Gem (24) (23).
All of the above varieties were chosen because
of their ability to survive for 21 weeks or more. If you can
spare a week or two, the following are the most commonly sold
varieties and their endurance (in weeks): Aaron (20), Blaze
(18), Fannie Munson (19), Festiva (20), Freida Hemple (18),
John Peed (18), June Bride (19), Lord Derby (18), Pink Beauty
(20), Pink Cloud (20), Red Flash (18), Rose Bud (18).
There are other superior varieties which should
be sold but are not commonly available. They include the "fancy
leaf" varieties Jubilee (25) (21), Pink Lady (22) (18)
and Sea Shell (23) (13). Other superior strap or "lance
leaf" types include Jackie Suthers (26) (17), Mumbo (23)
(16), Pink Symphony (23) (15), Red Frill (21) (11), and Lady
of Fatima (24) (14).
If you purchase one of these superior varieties
and want to try to save the tubers for planting next spring,
dig them in the fall and store them for spring replanting.
When foliage begins to yellow and daytime temperatures drop
and remain below 60 degrees F, the time is right to dig caladium
tubers. Air dry tubers for several days on a flat sunny surface.
Allow leaves to fall off by themselves. This way they keep
supplying tubers with needed nutrients.
Store tubers in dry peat moss or dry sand. Choose
a well ventilated spot where temperatures ideally remain between
70 and 75 degrees F. Do not refrigerate. Within 8 weeks new
growth may sprout, indicating tubers are healthy and prepared
in advance for spring garden action.