Competition is steadily increasing for
shelf/floor space in garden centers due to the ever-increasing
numbers of new plant lines and varieties. Caladiums can
withstand this competition and even grow in volume if well
grown. Caladiums are among the best buys for the consumer
-however, they needed to be attracted to the plants in the first
place. There aren’t many plants that are more attractive than a
well-grown caladium, though a poorly grown caladium can be a
real turn off. To produce a quality pot the nature of
commercial varieties must be understood. Current commercial
varieties are selected to survive and even thrive under Florida
conditions of high humidity, high temperatures and high (>9,000
foot-candles). To produce a quality pot these conditions must
be met OR things must be done culturally to compensate.
De-eyeing, spacing, good DIF (if possible) and growth retardants
go a long way in compensating for their needs.
The following are
our cultural suggestions for producing a highly marketable pot caladium
all bulbs sizes #2 and larger.
- Match bulb sizes and quantities to
the pot they are grown in.
Soak de-eyed bulbs for 20 minutes
in a 15-30 ppm (0.5 oz-1.0 oz/gallon) solution of Bonzi and
allow them to drip dry overnight on a greenhouse bench
(alternatively drench with 8 ppm at spike).
- Plant bulbs in a soil mix that
contains a slow release feed such as Nutricote, Osmocote or
Polyon. Your soil supply company should be able to take care
of this for you.Water the
planted pots and place pots in germination area (See
“caladium germination”) Alternatively weekly balanced liquid feed.
Drench with Subdue Max or other
fungicide that is effective against Pythium within 10 days of potting.
As you may know Subdue does come in a granular formulation that
can be mixed into your soil by your soil company saving you the
trouble of drenching. Repeat according to label.
- Place the pots in a very bright
growing location. Most varieties can stand 8,000+ foot-candles.
If the growing facilities allow for
good DIF control, better habits are achieved with 65-70°F nights
and 85-90°F days.
- Space pots at 3 weeks.
Alternatively, since caladiums have such short crop time space
them from the beginning.
- Spray plants with a 2500 ppm
solution of B-9, 5-7 days before shipping.
batches of bulbs, a Bonzi (8 ppm) drench (in stead of a bulb
soak) after the spikes are up has been found effective.
Drenches are only effective after there are roots to absorb the
material. 2500 ppm B-9 can be added to this drench solution to
cause thicker petioles.
Growth Regulators and Caladiums – general
Growth regulators such as B-9 and Bonzi have proven to be useful
for various growers around the country. Growth regulators do
not eliminate the need for good culture. We believe the best
height control for the pot plant trade is achieved by use the
proper de-eyeing technique, proper spacing (good light), timely
removal from bottom heat and selection of the proper bulb size
and variety for the finished pots you are trying to create and
use of growth regulators. In most cases, No. 2 bulbs produce
smaller leaves and a somewhat shorter plant. Of course too much
shade will cause stretching.
The following growth
regulators have been tried by various growers and research
institutes. Serious caladium growers should conduct similar
Apply when plants show a few spikes, and are not
yet leafed out at the rate of 8 PPM. Remember to wait for the
first spikes to show since only a well-developed root structure
will take up the Bonzi. The medium needs to be moist, not dry.
Pine bark in the mix will reduce the effect of a Bonzi drench
and the concentration will need to be increased by about 50%.
2500 ppm B-9 can be added to this to increase petiole thickness.
Soak tubers for 30 minutes after de-eying in a 8-30 ppm
(0.5oz-1oz/gal) Bonzi solution (#3 & #4= 0.25 oz/gal = 8 ppm; #2
& small #1= 0.5 oz/gal = 16 ppm; Large #1, J & M = 1.0 oz/gal =
32 ppm), allow bulbs to dry overnight on the bench and pot them
the following day. This will be effective in reducing the
height in cultivars like Aaron, Carolyn Whorton and White
Christmas and result in an overall more compact sturdier plant
for all varieties. As always, when using a drench or a soak,
the rate depends entirely on your growing conditions. Growers
should experiment to determine the proper rates and exposure for
3) Bonzi –
Some growers have found a Bonzi Spray at a
concentration of 1oz/gallon or 30 ppm effective in holding
plants. Addition of 2500 ppm B-9 to the Bonzi helps increase
petiole thickness and intensifies the colors.
4) B-9 -
Rate: 1 pound per 40 gallons of water, 2500 PPM
as needed; 5-7 days apart, two or three times when leafed out
and spaced. B-9 also makes for a very sturdy plant and improves
colors. 2500 ppm B-9 applied 7-10 days before shipping improves
the product at the retailer/consumer level.
5) Topflor and Piccolo
Recent (2007/08) studies by North Carolina
State University have shown soil drenches of 1-2 mg/ 6” pot to
be effective at controlling height in caladiums. Growers should
seriously consider experimenting with these materials.
Please Note: Mention of
pesticides, growth regulators etc. are by way of illustration
only not an endorsement. The label is the law therefore growers
must follow label directions with all regulated materials.
Furthermore, different cultivars respond differently to
treatments therefore try a small percentage of your crop before
applying a treatment to the entire crop. Mention of one product
does not preclude the use or benefit of other similar products.
Remember read the label and follow it.