A SURVEY OF CALADIUM CULTIVARS GROWN IN FLORIDA AND THEIR CHARACTERISTICS AS POTTED PLANTS

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1 Proc.Fla. State Hort. Soc. 95: A SURVEY OF CALADIUM CULTIVARS GROWN IN FLORIDA AND THEIR CHARACTERISTICS AS POTTED PLANTS Gary J. Wilfret IF AS, University of Florida, Agricultural Research & Education Center, th Street East, Bradenton, FL 508 : G. Tim Hurner, Jr. Highlands County Extension Service, Sebring, FL 870 Additional index words, phenotypes, aroids, culture, Cala dium x hortulanum Birdsey. Abstract.A survey of caladium growers in Highlands County, Florida, was made in 79 to determine the number of caladium cultivars grown and to ascertain the most pre dominant cultivars available. The most widely grown of 1 cultivars were '' (white), '' (rose), '' (pink), '' (red), and 'Postman Joyner' (red). Forty-two of the cultivars were propagated at only 1 farm. During and 81, 79 of these cultivars were grown in a polypropylene screenhouse and evaluated for their foliage characteristics and value as potted plants. Sixty-five cultivars were fancy leaved and 14 were lance leaved. Predominant leaf color ranged from white ('Candi dum') to dark red (''). Leaf number ranged from 5.1 ('Jubilee') to 41. ('') and plant height varied from.4 inches ('') to 20.5 inches ('Jubilee'). Pot value (scale of 1-5) ranged from a low of ('Jubilee') to a high of ('') with cultivars attaining a value of.0 or higher. Caladiums (Caladium x hortulanum Birdsey), New- World tropical ornamentals grown for their colored foliage, are used as potted and landscape plants during the warm seasons of the year. They are grown primarily from tubers produced almost exclusively in the muck soils of the Lake Placid-Sebring area of central Florida, where approximately 0 acres were planted in 81. Caladiums are available in a multitude of leaf colors and patterns, plant heights, and leaf shapes and sizes (2) from hybridization efforts which started in the late 1800's using C. bicolor (Ait.) Venten, C. picturatum C. Koch & Bouche, C. Schombungkii Schott, and possibly other species (1, ). Although up to 1500 cultivars may have been introduced during the past 0 yr (, ), only 141 are listed presently in Exotica (4), and some of these are no longer produced commercially in Florida. In formation is available on the curing, storing, and forcing of caladiums (, 5, 7) and their value as indoor and outdoor plants (8, 9), but few descriptions of the cultivars, except for leaf color patterns (4), are recorded when caladiums are grown as potted plants. Objectives of this study were to determine which cala dium cultivars are grown commercially in Florida and to record the phenotypic characteristics of the available cul tivars when grown as potted plants. Materials and Methods Survey of cultivars grown. Discussions with selected com mercial caladium propagators in the Lake Placid-Sebring area of central Florida indicated that 78 cultivars were thought to be grown in 79. A survey sheet was prepared listing these cultivars in alphabetical order with blank spaces at the end for additional cultivars. This sheet was then sent to growers with instructions to indicate which of the 78 cultivars they propagated during 79 and to add any cultivars which they grew but were not listed. Thirtyone of the caladium producers returned the forms and the cultivars and their frequency of production were tabulated. Cultivar evaluation. Based upon the results of the survey, 79 caladium cultivars were provided by commercial propa gators and were grown during the spring season of and 81. Since all cultivars identified in the survey were not available during both and 81, only those cultivars which were available during both years were included in the evaluation study. Jumbo (^ <.5 inches diameter) tubers were planted in inch diameter plastic pots (RT 00). The medium consisted of a mixture of Florida Peace River peat, coarse white builders' sand, coarse vermiculite, and perlite (5:::1, by volume). Each pot had four 0.8 inch diameter holes in the bottom and four 0.5 x 0. inch holes at the base of the sides. Amendments, per cubic yard of medium, were 1.2 lb. Osmocote (N, P2O5, K2O), 20.0 lb. dolomite, lb. hydrated lime,.0 lb. superphos phate, and lb. Perk (a minor element mixture). Initial ph was. Pots were placed on capillary mat beds in the shade house covered with black polypropylene (25% shade). Water was distributed on the Vattex capillary mat with 2 Chapin twin-wall tubes (4 inch hole spacing) spaced 12 inches apart down the length of the 2 inch wide bed. The mat and tubes were covered with a 1.25 mil white-on-black polyethylene mulch with the white side up. Plants were set across on the beds, with the center row staggered from the outer two. Pots were spaced on 1 inch centers and the poly ethylene under each pot was cut and discarded. The capil lary mat was irrigated at 8 AM, noon, 4 PM, and midnight in an amount to thoroughly wet the mat without runoff. The experimental design was a randomized complete block and each cultivar was replicated times with pots per ex perimental unit. In the tubers were planted on May 12 and the plants were evaluated on July 21. In 81 the tubers were planted on May 12 but were not evaluated until August. Data weiie recorded on number of leaves, leaf type, max imum leaf size, maximum plant height above the pot rim, petiole color, and leaf color and pattern. Each pot was given a value rating of 1 to 5 based upon the proportion of the plant to the container, the fullness of the plant, and the color retention and quality of the foliage. A value of 1 in dicated a poor plant with either few leaves or weak stems, and a value of 5 was indicative of a plant with many leaves of good color and approximately inches tall. Special consideration on height was given to some of the lance-leaf cultivars which normally are no taller than inches. Results and Discussion iflorida Agricultural Experiment Stations Journal Series No sappreciation is expressed to the caladium growers of Highlands County for providing the tubers, and to the Fred C. Gloeckncr Founda tion for partial support of this research. 0 Caladium survey. The caladium cultivars propagated in Florida are listed in Table 1. In addition to the 78 cultivars enumerated on the survey circular, 2 additional cultivars Proc.Fla. State Hort. Soc. 95: 82.

2 were reported, for a total of 1. Of these, 2 sets were recog nized as the same cultivar with different names. '' and '' are the same and 'Becky Sheppard' and '' are identical. Forty-two of the cultivars are propa gated by only 1 grower (not always the same farm) and 7 are found on 2 farms. '' was the only cultivar grown on all 1 farms that returned the questionnaire (Table 2). The most frequently grown fancy leaved cultivars, separated by predominant foliage color, are: '' and '' (white); '' (rose); ',' '/ and '' (pink); and '' and ' (red). '' (red), '' (White), and '' (red) are the most frequently grown lance leaved cultivars, with 2, 1 and % of the farms propagating these. Cultivar evaluation. Leaf characteristics of the 79 cul tivars evaluated are recorded in Table 2. Sixty-five cultivars are classified as fancy leaved, distinguished with leaves hav ing a width generally 2/ that of their length. The remain ing cultivars are lance-leaved, with the tip of the leaf narrow and pointed. Several cultivars, such as '' and '' are intermediate in leaf shape but are placed in the lance group. 'Etta More,' with white leaves, pink spots, and cream-rose venation, has the most extreme lance-type leaf. A third section, called "strap-leaved" by the growers, should be included in the identification of caladium cultivars. 'Etta More' and cultivars with similarly elongated leaves should be in this classification. Caladium leaf margins are various shades of green, rang ing from the almost yellow of '' to the dark green of '.' As would be expected, the green color varies relative to the light intensity in the production area. Width of the green margins can be very narrow, as ex hibited by ',' to very broad, as displayed by '' and 'Poecile Angais/ Leaf color patterns can be categorized as follows: White interveinal netted (''); white, pink, or rose spots (''); colored, central area (''); and distinctly colored main veins (''). Modifi cations and combinations of these patterns were observed in all of the cultivars evaluated (Table 2). For example, 'Car olyn Whorton' has both pink and white spots with dark red main veins on a dark green background and 'Mrs. Arno Nehrling,' when grown under reduced light intensity, dis plays a white netted pattern with narrow dark red main veins. 'Jubilee' has a similar white speckled center as '' with the addition of pink spots. Many cultivars with pink or rose spots in the juvenile foliage have almost solid pink or rose mature leaves due to coalescence of the spots. Some, like '' (rose) and '' (pink), are translucent. Unfortunately, under high light intensities, these translucent areas fade or burn, which distracts from the overall quality of the plant. Of the 79 cultivars evalu ated, were rose, were pink, 1 were white, 1 were red, and 2 were predominantly green. Petiole color ranged from light green ('') to very dark brown ('Crimson Wave'), with various shades of green, rose, and brown superimposed on the base color. In general, cultivars with darker colored petioles had more upright foliage. Number of leaves, which is very important in the mark etability of the potted plant, ranged from 5.1 ('Jubilee') to 41. (''), with a mean of 1 leaves per plant for both seasons (Table ). The lance leaf cultivars generally had more leaves than the fancy leaved ones. Three distinct growth patterns were evident with the cultivars: 1) terminal dominance, where 1 or 2 large leaves develop followed by smaller leaves to 4 wk later ('' and 'Jubilee'); 2) incomplete terminal dominance where 1 or 2 large leaves develop in the center and smaller leaves develop on the periphery of the tuber ('' and ''); and ) no dominance, where 8 to leaves develop simul taneously from the tuber ('' and 'Tom Tomlinson'). The "no dominance" type of growth produces the fullest plant and the earliest to market. Height of the plants is another factor in the overall marketability of the cultivar. Since these plants were grown in 5 inch high containers, an ideal plant to pot ratio should be :1, or 1 inches. A height range of -14 inches was acceptable. Height of the cultivars ranged from.4 inches ('') to 20.5 inches ('Jubilee'), wth 42 of the cultivars within the acceptable range. Plants which were too tall, such as 'Jubilee' and ',' often toppled during watering or adverse weather conditions. Some of the shorter cultivars, such as '' and 'Etta More,' would be more adapt able to smaller pots, hanging baskets, or the outer perimeter of large containers which contained a mixture of cultivars. The value of a cultivar when grown in a inch pot was determined by its leaf number, height, petiole strength, earliness to show color, and color retention. Although this was a subjective evaluation, the ratings between and 81 were relatively consistent for each cultivar. The rat ings ranged from a low of ('Jubilee,' which was too tall Table 1. List of caladium cultivars reported propagated commercially in Florida in 79z. Avalon Rose Becky Sheppard Blue Gem Caloosahatchee Jr. Carolyn Jones D-4 Daybreak Edna Elizabeth Dixon Elizabeth Lou Elisa Still Etta More Festivia Florida Beauty Fred Bause Gail Dee Jackie Slithers Jessie Thayer John Peed Jubilee June Bride Whorton Machyba New John Peed Pink Calla Pink Glow Pink Seashell Pink Triumph Pothos Red Empro Ruby Smith Scaracoba Smith Red Sonya Marie Texas Wonder Tisa Moir Tommy Tom Tomlinson Triomphe de L'Exposition W. B. Sanders White Knight White Prince zbased upon a survey sent to caladium propagators with 1 responses. Proc. Fla. State Hort. Soc. 95: 82. 1

3 Table 2. Frequency of caladium cultivars propagated in Florida and their leaf characteristics. Cultivar Leaf type Leaf characteristics Margins Center Main vein Petiole color Growers* Ranky Caloosahatchee Junior Etta Moore Festivia ~ackie Suthers ohn Peed ubilee une Bride Whorton (BH) (H) Tom Tomlinson Triumph de L'Exposition Pale Pale Creamy white rose green blotches -red Red w/spots -red Rose fingered veins Lg. pink spots rose spots Pink & white spots spots Smoky rose overlay Blush white rose spots rose spots rose spots spots Rose w/rose spots Med. red Dk. rose w/rose spots Cream green rose-red White w/white spots pink w/pink spots Dk. rose w/rose spots w/rose spots rose spots Dk. pink w/pink spots spots w/rose spots pink spots Lg. dk. rose spots Smoky med. rose pink spots pink spots Lt. pink & White spots Med. dk. rose red Dk. rose w/red spots Med. burgundy Rose w/green blotches Rose w/pink spots Red w/sm. white spots pink spots Dk. rose w/white specks w/green specks Dk. rose w/green specks White blotches blotches White speckled Rose w/rose spots rose spots rose spots red rose spots rose Rose w/dk. pink spots Rose w/white interveins White blotches Many white spots White speckles pink spots rose rose rose rose red red Cream red pink green Creamy rose rose green red red rose red red rose Med. pink red Lt. rose green red green rose rose rose red red green green pink pink rose red red rose red rose rose rose rose red rose green rose green red Pale rose green brown -brown brown green brown green green -rose brown brown brown -rose Lt. Brown brown -brown -rose -rose brown brown green Brown-rose brown Brown-rose -brown green green green -brown T 5T 8T 1 2T T 5T T T 5T 2 1T T 5T 11T 5T 20 1T 25 T 18 2T T 15 5T 1T 1ST 1T 8T 2T 5T 8 ^Percentage based upon the number of growers who propagate the cultivar as established from the survey of propagators with 1 respones. yrank is the order of frequency (from high to low) each cultivar was reported grown; "T" = tie. 2 Proc. Fla. State Hort. Soc. 95: 82.

4 Table. Plant characteristics of caladium cultivars and their value as pot plants. Cultivar Number leaves^ Plant height (inches)z Leaf size (inches)y Length Width Pot value* Caloosaha tehee Carididum Junior Etta Moore Fes ti via Jakie Suthers John Peed Jubilee June Bride Whorton Tom TomJinson Triumph de L'Exposition Mean LSD (0.05) , ,8 i n.4.1 1, o a.0 : IA zmean of replications consisting of plants each (jumbo tuber planted). ylargest leaf measured in each pot. xvaiue of 1 is poor; is acceptable; and 5 is excellent. Proc. Fla. State Hort. Soc. 95: 82.

5 and had few leaves) to (',' which had many upright leaves with good color retention). A value of or above was considered acceptable and of the cultivars at tained this value. The most frequently grown cultivars (Table 2) have a combined value of.4, the next have a combined value of, and the next have a value of only. Since over 80% of the caladium tubers sold are forced in pots, the relationship between pot value and grower fre quency was expected. This indicates that caladium propa gators either are cognizant of the cultivars which are most adaptable to pot culture and grow these more than the other cultivars, or they are simply growing those cultivars in greatest demand. In either case, frequency of production of the cultivars is related to their value as potted plants. Caladiums can add beauty to the indoor and outdoor landscape as potted or bedding paints and can be grown in shaded as well as sunny locations. Selection of the correct cultivar for specific growing conditions is essential for max imum effect. The characterization of the 79 cultivars re ported should make this selection easier for the grower and consumer* Literature Cited 1. Birdsey, M. R. 51. The Cultivated Arioids. The Gillick Press, Berkeley, CA. 0 pp. 2. Black, R. J. and B. Tjia. 81. Caladiums for Florida. Fla. Coop. Ext. Ser. Cir pp.. Conover, C. A. and R. T. Poole. 7. InBuence of shade level and soil temperature on forcing of Caladium bicolor. Proc. Fla. State Hort. Soc. 8: Graf, A. B. 70. Exotica Third. Roehrs Co., E. Rutherford, N.T. pp Harbaugh, B. K., F. J. Marousky, J. F. Price, and D. J. Schuster. 79. Guidelines for forcing caladiums. Florida Ornamental Grow ers' Assoc. Newsletter 2:4-5.. Hayward, W leaved caladiums. Plant Life : Marousky, F. J. and J. C. Raulston. 7. InHuence of temperature and duration of curing, storage, shipping, and forcing periods on caladium growth. Proc. Fla. State Hort. Soc. 8: Smith, P. W.. Caladiums indoors and out. Organic Garden ing & Farming (2): Wilfret, G. J. 82. Caladiums for Florida gardens. Florida Garden Guide, March/April, pp Zettler, F. W. and M. M. Abo El-Nil. 79. Mode of inheritance of foliage color in caladium. J. Heredity 70: Proc. Fla. State Hort. Soc. 95: 82.