Group Title: ARC-A research report - Agricultural Research Center-Apopka ; RH-73-3
Title: Factors influencing forcing of caladiums
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 Material Information
Title: Factors influencing forcing of caladiums
Series Title: Apopka ARC research report
Physical Description: 6 leaves : ; 28 cm.
Language: English
Creator: Poole, R. T ( Richard Turk )
Conover, Charles Albert, 1934-
Agricultural Research Center (Apopka, Fla.)
Publisher: University of Florida, IFAS, Agricultural Research Center
Place of Publication: Apopka Fla
Publication Date: 1973
Subject: Caladium -- Growth -- Florida   ( lcsh )
Growth (Plants) -- Control -- Florida   ( lcsh )
Genre: government publication (state, provincial, terriorial, dependent)   ( marcgt )
non-fiction   ( marcgt )
Statement of Responsibility: R.T. Poole and C.A. Conover.
General Note: Caption title.
 Record Information
Bibliographic ID: UF00065953
Volume ID: VID00001
Source Institution: University of Florida
Rights Management: All rights reserved by the source institution and holding location.
Resource Identifier: oclc - 70922168

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The publications in this collection do
not reflect current scientific knowledge
or recommendations. These texts
represent the historic publishing
record of the Institute for Food and
Agricultural Sciences and should be
used only to trace the historic work of
the Institute and its staff. Current IFAS
research may be found on the
Electronic Data Information Source

site maintained by the Florida
Cooperative Extension Service.

Copyright 2005, Board of Trustees, University
of Florida


. "- F R. T. Poole and C. A. Conover '
University of Florida, IFAS \
Apopka ARC Research Report RH73-3 p

Caladiums, members of the popular ornamental family of Araceae, ae ende c to \

tropical America, primarily in the hot humid Amazon basin. Today, cal dUm tubers

are produced in Florida around the Sebring Lake Placid area with some u

near Lake Apopka. Most tubers are used for forcing potted plants to be sold during

the spring and summer. Easter and Mother's Day are popular times to sell caladiums.

Timing of caladiums to produce plants for these dates is a problem because of

varying durations necessary to produce attractive plants. Time of digging tubers,

time and treatment during storage and cultural practices influence time required and

quality of plants. Research at the Agricultural Research Center-Apopka indicates

that tubers of 'Scarlet Pimpernelle' and 'Candidum' dug in November (11/12/71) will

produce salable plants approximately one half to one and a half weeks earlier

(Table 1) than tubers dug in December (12/12/71).

Table 1. Influence of digging time on weeks required to produce
salable plants.

Weeks from potting to time of sale
Digging Time Candidum Scarlet Pimpernelle

Nov. 12, 1971 8.0 7.8

Dec. 12, 1971 8.6 9.3

After digging the tubers, storage temperature and humidity are extremely

important. "Temperature should not be allowed to drop below 650F and 700 appears

to be most satisfactory. Storage in a heated well ventilated area reduces incidence

of tuber rot and appears to reduce dormancy.


The length of time plants are kept in storage determines the time required to

produce salable plants. Tubers planted approximately 3 months after digging needed

two or more weeks to be ready for sale than tubers planted 5 months after digging

(Table 2).

Table 2. Influence of duration of tuber storage on time (wks) required
to produce salable plants.

Time (months) in storage
Cultivar 3 33 4 4 5

Scarlet Pimpernelle 9.6 8.6 B.3 7.7 7.3

Candidum 10.0 8.8 8.1 8.1 7.6

Caladiums appear to grow best in a well drained well aerated medium. Tubers

grow very well in clean 100o acid peat. Other material such as sterilized soil,

sand, perlite or vermiculite may be used on a 1/1 volume basis with peat.

Fertilizer is not necessary to produce salable plants when tubers are not

scooped or inverted, although slight increases in quality can be obtained (Table 3).

However, if tubers are scooped and/or inverted the equivalent of 1 to 2 teaspoons

of 14-14-14 Osmocote should be utilized to obtain satisfactory quality. Many

other species of plants have shown excellent response to Osmocote, but evidently

with caladium tubers, enough food is stored in the tuber to produce sufficient

foliage. However, if an increase in tuber size is important, fertilization will be



Table 3. Influence of fertilizer on growth of caladiums.

Fertilizer Candidum Red Flare
14-14-14 Osmocote # breaks, Leaf length # breaks Leaf length
(cm) (cm)


0 33 12.9 36 12.3

1/2 teaspoon/6" pot 34 13.0 36 12.4

---------------- 7-----------------------------------------

Candidum Spangled Banner


0 16.5 31.7 19.3 25.9

1 teaspoon/6" pot 20.2 23.9' 21.9 27.1

2 teaspoons/6" pot 19.7 29.5 22.0 26.1

To scoop or not to scoop? To invert or not to invert? These two questions

bring varied responses from growers who f6rce caladiums. Foliage will rise and

roots will descend whether the tubers are scooped, dissected, placed right side

up, upside down or side ways. However, planting position and/or scooping will

influence number and size of leaves. In general, fewer and larger leaves arise

if neither scooping nor inversion is utilized and grade is improved if plants are

placed upright.(Table 4).

STable 4. Influence of scooping (eye removal), and position on growth aridgrade (1-5)
of caladiums.

Candidum Red Flare
No. Leaf Plant No. Leaf Plant
breaks length grade breaks length grade
Treatment (cm) (cm)

No scooping 29.8 14.6 4.2 30.0 14.2 3.1
Scooping 37.2 11.9 3.3 41.5 10.5 2.9
S Candidum Spangled Banner
No scooping 15.4 32.0 3.4 15.3 30.0 2.9
Scooping 22.2 23.0 3.7' 26.9 22.3 3.3

Upright 15.4 29.5 4.2 22.2 27.5 3.7
Inverted 22.2 30.5 3.0 19.4 25.5 2.5

Watering practice during forcing is very important. Tubers should be kept moist

at all times; however, excess moisture may induce tuber rots. As leaves emerge,

watering frequency should be increased. The soil should never feel dry.

Warmth is important during gCowth of caladiums just as it is during storage of

the tubers. Temperatures of at least 700F are necessary and higher temperatures

are not detrimental (Table 6). Temperatures below 70 F should be avoided. Increasing

soil temperature above a minimum of 70 did not decrease time required to produce a

salable plant (Table 6).

Table 6. Influence of temperature on growth and time to sale of caladiums.

1971 Growth
Minimum Candidum Red Flare
Soil Temp (F) No. breaks Leaf length No. breaks Leaf length

70 33.8 13.0 36.1 11.8
80 34.8 13.0 34.7 12.1
90 32.1 13.7 39.0 13.1

1972 Peeks to Sale
Candidum Scarlet Pimpernelle

70 8.6 8.3
80 8.4 8.1
90 8.8 8.4

Light can influence the quality of the potted caladium plant. Low light will

produce plants of poor quality as will high light. Five thousand foot candles will

produce good quality plants, although different cultivars require optimum light

(Table 7).


Table 7. Influence of light level on growth and quality of caladiums.

Leaf Plant Plant
length height grade
Foot Candles (cm) (cm)


12000 (full sun)



Crimson Wave

12000 (full sun)

-Spangled Banner

12COO (full c-.,n)






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