1. Always know when the tubers
were dug, as the tubers require an 8 week storage period after digging
before they will grow.
2. Make sure tubers have been
stored and shipped at temperatures above 70° F. Soft, rubbery tubers
indicate cold damage and tubers will not grow properly.
3. De-eye the tubers (removal
of a very small central portion of the dominant buds) to produce more,
although smaller, leaves, and yield a fuller plant. Some cultivars (including
Candidum Jr. and Florida Sweetheart) do not need this treatment, and
the smaller leaves may not be desirable in large pots or some landscape
4. Plant tubers upright in
a well-drained, moist medium with a high organic content for moisture
retention and a pH of 5.5 to 6.5. Cover the tubers with 1.5 to 2 inches
of medium, since roots develop on the upper surface of the tubers.
5. Fertilize tubers with a
liquid feed program of 400 ppm N-P-K weekly after first leaves appear
or incorporate 1 lb N/cu yd of a slow release fertilizer in the medium.
6. Most cultivars produce
optimum growth and color at 2,500 to 5,000 ft-candles of light.
7. Grow plants at 70-90° F
with high humidity and never let plants dry to the wilting point.
8. Plants are generally marketable
5 to 8 weeks after planting, depending upon the pot and tuber size used.
The time needed is reduced as the heat of summer comes into play.
9. Tuber sizes (by diameter)
used for containers are:
#2 0.75 to 1.5 inches
#1 1.5 to 2.5 inches
Jumbo 2.5 to 3.5 inches
Mammoth 3.5 inches and up
10. Number of tubers used
4" pot 1 or 2 #2’s; 1 #1
6" pot 5 to 6 #2’s; 3 #1’s;
1 to 2 Jumbo tubers
10" pot (pan) 10 to 12 #2’s;
5 to 6 #1’s; 3 to 4 Jumbo tubers
10" hanging baskets 10 to
12 #2’s; 5 to 6 #1’s; 3 to 4 Jumbo tubers
11. Caladiums generally have
no foliar disease problems, but insect pests can include armyworms and
loopers, aphids, mealy bugs and occasionally mites. These can be controlled
using labeled products, but try to avoid emulsifiable concentrate formulations.
12. Plants should be shipped
at temperatures at or above 70° F and retailers must be educated about
the cold sensitivity of the plants and their need for lots of water.
Any nursery looking for a
good hot-weather crop should try caladiums. Their diversity of color
and leaf types make a colorful addition to spring and summer pot sales
and also are a welcome addition to dry-bulb sales in retail outlets.
Dr. Michelle Bell and Dr.
Gary Wilfret of the University of Florida Gulf Coast Agricultural Research
and Education Center, Bradenton, FL provided the information and illustrations
for these stories.
Caladiums in the Landscape
Table of Contents