Gulf Coast Research and Education Center

Richard O. Kelly[1], Rick Schoellhorn[2], Zhanao Deng[3], and Brent K. Harbaugh[4]

Summary. We evaluated 70 cultivars of petunia (Petunia x hybrida) in replicated class tests at the University of Florida Gulf Coast Research and Education Center at Bradenton, Fla. [lat. 27.4 N, long. 82.5 W; AHS Heat Zone 10; USDA (American Horticultural Society, 1999); USDA Cold Hardiness Zone 9b (U. S. National Arboretum, 1990)] in the spring/summer of 2002. In this report we provided objective plant measurements of vegetative and flower characteristics, earliness of flowering, flower divergence (Table 1), as well as subjective ratings that permit readers to evaluate foliage and flower characteristics (Table 2, sprayed field) and the affects of pests (Tables 3 and 4, unsprayed field) at different times during the season, and to evaluate performance over time. Subjective ratings were on a scale from 1 to 7 with the highest rating of 7 for excellent. Cultivar performance in this trial was good in most classes; no cultivar exhibited poor overall performance. As a result, cultivar performance standards were very high in this trial, with adjusted overall performance ratings > 6.0 being considered outstanding, 5.5-5.9 as very good, 5.4-5.0 as good and 4.0-4.9 as fair, and < 4.0 as poor. Cultivars were grouped into classes based on species or hybrid type, plant type (such as growth habit), plant height, flower type (doubles and single forms) and flower color, and are listed here by performance within class.

Outstanding cultivars (> 6.0) were: [Millifloras] ‘Fantasy Light Lavender’ [single purple, blue violet (light) class]; [Spreading Types] ‘Wave Blue’ [single blue (dark) class]; ‘Explorer Rose Pink’, ‘Explorer Pink’ and ‘Wave Pink Improved’ (single pink class); ‘Easy Wave Shell Pink’ [single pink (light) class]; ‘Avalanche Lilac Improved’ [single purple, blue-violet (light) class]; ‘Explorer Purple’ [single purple, red-violet (dark) class]; ‘Opera Light Purple’ [single purple, red-violet (dark) class]; ‘Explorer Magenta’ [single purple, red-violet (very dark) class]; ‘Explorer Rose’ and ‘Opera Deep Rose ‘ (single rose class); ‘Ramblin' Peach Glo’ [single salmon (light) class]; ‘Kahuna Violet’ [tall - Single purple, red-violet (very dark) class]; and ‘Kahuna White’ [tall - Single white class].

Very Good cultivars (5.5-5.9) were: [Floribundas] ‘Celebrity Mid Blue’ (single blue class); ‘Clear Madness Mix’ and ‘Waterfall Madness Mix’ (single mix class); ‘Celebrity Chiffon Morn Improved’ (single pink class); ‘Magenta Madness’ [single purple, red-violet (dark) class]; ‘Celebrity Rose’ (single rose class); [Grandifloras] ‘Storm Blue’ [single blue (dark) class]; ‘Storm Lavender’ [single purple, blue-violet (light) class); ‘Storm Violet’ (single purple, red-violet (dark) class]; ‘Ultra Salmon’ (single salmon class); [Millifloras] ‘Fantasy Mix’ (single mix class); [Multifloras] ‘Hurrah Pink Chiffon’ (single pink class); ‘Primetime Violet Star’ (single purple/white class); ‘Symphony Rose’ (single rose class); [Spreading Types] ‘Explorer Blue’ and ‘Ramblin' Nu Blue’ [single blue (dark) class]; ‘Easy Wave Pink’ and ‘Ramblin' Shades O' Pink’ (single pink class); ‘Avalanche Lavender’ and ‘Explorer Lavender’ [single purple, blue-violet (dark) class]; ‘Opera Deep Purple’ [single purple, red-violet (very dark) class]; ‘Avalanche Cherry’, ‘Avalanche Red’, ‘Avalanche Tropical Red’ and ‘Easy Wave Cherry’ (single red class); ‘Avalanche Rose’ (single rose class); ‘Ramblin' Deep Salmon’ [single salmon (dark) class]; ‘Avalanche Salmon’ [single salmon (light) class]; ‘Avalanche White’ and ‘Explorer White’ (single white class); ‘Ramblin' Misty Lilac’ [tall - Single purple, blue-violet (light) class]; and ‘Ramblin' Burgundy Chrome’ [tall - Single purple, red-violet (dark) class].

Good cultivars (5.4-5.0) were: [Floribundas] ‘Celebrity Burgundy Improved’ [single purple, red-violet (dark) class]; ‘Celebrity White’ (single white class); [Grandifloras] ‘Aladdin Pink Morn’ and ‘Storm Pink Morn’ (single pink class); ‘Aladdin Strawberry Ice’ (single purple, blue-violet (light)/red class); ‘Aladdin Burgundy Improved’ [single purple, red-violet (dark) class]; ‘Aladdin Cherry Improved’ (single red class); ‘Bravo Salmon Improved’ and ‘Storm Salmon’ (single salmon class); ‘Storm White’ (single white class); [Multifloras] ‘Old Glory Mix’ (single mix class); ‘Symphony Red Picotee’ (single red/white class); ‘Symphony Rose Picotee’ (single rose/white class); [Spreading Types] ‘Ramblin' Neon Rose’ (single rose class).

Acknowledgments

This research was supported by the Florida Agricultural Expt. Station, and donations of money, seeds, fertilizer, potting soil and plant containers from the following companies: American Takii Seed, Ball Seed Company, Bodger Seeds, Ernst Benary of America, Floranova, The EarthBox, Flower Fields-Goldsmith, Kieft Seeds Holland, PanAmerican Seed, Sakata Seed America, The Scotts Company, Speedling, and Syngenta Seeds. We thank Joyce Jones, Nancy West and Gail Bowman for their excellent technical support.

Introduction

     The United States wholesale value ($1.00 = € 0.856311, 19 June 2003) of floricultural crops was $ 4.9 billion (€4.2 billion) 
in 2002, estimated from growers with sales ≥ $10,000 (€8,563).  Bedding and garden plants comprise 46% of the floriculture 
value at $2.3 billion (€2.0 billion), up 5 percent from the previous year. The wholesale value (2001/2002) of the top five bedding 
plant producing states was: Florida ($91/101 million; €77.9/86.5 million), ranks fifth behind California ($254/251 million;
 €217.5/€214.9 million), Texas ($154/164 million; €131.9/140.4 million), Michigan ($143/153million; €122.5/131 million), and 
Ohio ($104/98 million; €89.1/83.9 million), and together these states generate 42% of the bedding/garden plant wholesale value 
(United States Department of Agriculture, 2003).  In the 1997 Census of Agriculture, petunia was ranked second ($77 million; 
€65.9 million) and seventh ($11 million; €9.4 million) in the United States for wholesale value in flat and pot culture, respectively.     
In 2002, the value of bedding and garden flats was down 3 percent ($843 million; €121.9 million), with petunias ranked as one 
of the top 3 crops.  Potted bedding and garden plants wholesale value was 11 percent above 2001 ($1.21 billion; €1.0 billion), 
with petunias being one of the crops experiencing an increase in this category (United States Department of Agriculture, 1998 
and 2002).

This study was conducted to evaluate petunia performance in a seasonal replicated trial that may be used by growers, landscapers, consumers and seed companies as well as the scientific community.

Materials and Methods

Seeds of 70 cultivars of petunia were sown between 8 and 14 Feb. 2002 into a soil mix containing peat, vermiculite and perlite (3:2:1, volumetric) prepared and amended with dolomite 7 lbs./yd³ (3.2 kg/m³), gypsum 3 lbs./yd³ (1.4 kg/m³) and Micromax (Micromax, The Scotts Co., Marysville, Ohio) 1.0 lb./yd³ (0.45 kg/m³). This mix was used to maintain compact transplants, supplying phosphate only through soluble fertilizer applications. Germination occurred between 72 to 75 °F (22 to 24 °C) in a growth room with a photosynthetic photon flux of 30 μmol·m^-2·s^-1 for 24 hours from cool-white fluorescent lamps. Immediately after germination, seedlings were transplanted into Todd^â planter flats [model 128: 1.5 inches x 1.5 inches x 2.5 inches (3.8 cm x 3.8 cm x 6.4 cm) cells; Speedling Incorporated, Sun City, Florida] containing the same soil mix used for seed sowing, and placed into a screen-sided, fiberglass-covered greenhouse. Seedlings were fertilized with a 15N-0.87P-16.5K water-soluble fertilizer (15-2-20 Ca-Mg Excel; Scotts Co., Maryville, Ohio) solution applied at the rate of 50 to 250 mg·L^-1 twice weekly. Fertilizer concentrations were adjusted during seedling development to meet the requirements for petunias.

Petunia plugs were transplanted into raised ground beds between 1 and 2 April. Plants were arranged with five plants/plot, having one plant in the center of each plot and four plants spaced 12 to 15 inches (30.4 to 38.1 cm) equidistant from the center plant. Space between plots ranged from 1.3 to 4.7 feet (0.4 to 1.4 m), depending on petunia type. All petunias were grown in full sun in beds that were 32 inches (81.3 cm) wide x 8 inches high (20.3 cm), spaced 5 ft. apart from center. Beds were fumigated 15 Feb. (full sun crops) and 12 March (shaded crops), > 14 days prior to planting, with a mixture of 66% methyl bromide and 33% chloropicrin at 392 kg·ha^-1 (350 lb/acre) and covered with white-on-black polyethylene film. Irrigation water was supplied through subsurface seepage irrigation from lateral ditches spaced 12.8 m (42 ft) apart. Osmocote Plus^® 15N-3.9P-9.9 K fertilizer [15-9-12 (5-6 mo.) slow release type with micronutrients; The Scotts Co., Maryville, Ohio)] was applied by hand to each plant on the soil surface approximately an inch from the plant stem under the plastic mulch at 262 lb/row acre (294 kg·ha^-1) of nitrogen (Kelly et al., 2002).

Integrated pest management was employed to determine when pesticide applications were needed to control arthropod pests and plant pathogens. Temperature @ 2 ft (61.0 cm) during the experiment ranged from a low of 10.3 °C (55 °F) to a high of 34.3 °C (94 °F) from 25 March to 15 July. Total rainfall of 51.1 cm (20 inches) occurred from 25 March to 15 July. No rain fell in March, while 63% [32.0 cm (12.6 inches)] fell between 1 June to 15 July.

Three plants per plot were selected on 30 April (spreading type) and 13 May (florabunda, grandiflora, milliflora and multiflora) from the center and edge of each plot, and the plant height (from the stem base to the inflorescence tip), plant width and flower diameter were recorded. Plants in each plot were selected from the same positions in that plot. Days from sowing to first open flower and flower divergencewere recorded. Flower divergence represents the number of days required for the first and last plant in a plot to unfurl their flowers in a plot. Subjective ratings for foliage and flower quality were made for each cultivar within classes on 1 to 2 May and 1 to 2 June. Average foliage and flower ratings represent relative cultivar quality within a class, measured in a field sprayed on demand, following pest scouting. Pest symptoms were rated on 23 to 25 May and 5 to 7 June in an unsprayed field (simulating a homeowner environment). Where necessary, the causal agents were confirmed by a plant pathologist or entomologist. Each cultivar was rated on a 1 to 7 scale with the highest rating of 7 for excellent. Plant characteristics that merited a 7 were: (1) all plants in a plot had full and uniform foliage; (2) foliage and flowers were free of pest symptoms; (3) plants were free of abnormalities or weaknesses such as lodging; and (4) flowers were numerous and uniformly distributed over the plant.

In order to provide meaningful performance comparisons, cultivars were divided into classes based on color and plant growth habit. Color hues with similar shades and tints were grouped together into one class.

The choice of best of class for petunias in spring 2002 was determined by comparing the overall performance ratings. This value was arrived at using the formula OP = (Q + P)/2, where Q = (foliage rating avg. + flower rating avg.)/2 under the Table 2 heading “overall foliage/flower rating”, and P = overall pest rating (Table 4). The number of dead plants from soilborne pathogens was not a factor for this species, therefore an adjusted overall performance (OP_adj) value, which accounts for plant death due to disease, was not necessary. The cultivar with the highest overall performance received best-of-class honors. Differences in these ratings may not be statistically significant. If two or more cultivars had equal overall performance ratings, another rating category, such as overall foliage/flower ratings (Table 2), was used to make the choice, and so forth, until a better performer was selected. This type of choice is necessary in order to select a single cultivar every season as the standard by which all others in the class may be compared in future seasons, thus limiting the number of cultivars necessary in a trial. If a class only contains one cultivar, that cultivar becomes the uncontested best of class.

Each class was analyzed as a separate experiment. A randomized complete block experimental design was used with three blocks each containing six plants that represented the experimental unit. All data were analyzed by analysis of variance (ANOVA) methods, and means of dependent variables significant at the 0.05 level of probability were separated using Duncan’s multiple range test (PROC ANOVA, SAS Institute, Cary, North Carolina).

Results and Discussion

Floribundas

Double pink class. ‘Double Madness Pink’ had a flower diameter of 5.6 cm (2.2 inches), and the first bloom opened 61 days after sowing. The overall rating for foliage/flower quality was 5.5. There were no plants available in the unsprayed field for a pest evaluation; however, pest ratings for the entire floribunda group and all other petunia groups were generally very high. ‘Double Madness Pink’ is uncontested best-of-class.

Single blue class. ‘Celebrity Mid Blue’ had a flower diameter of 5.2 cm (2.0 inches), and the first bloom opened 63 days after sowing. The overall rating for foliage/flower quality was 5.3, and the overall pest rating was 6.1. The overall performance rating was 5.7. ‘Celebrity Mid Blue’ is uncontested best-of-class.

Single mix class. Flower diameter was 5.5 cm (2.2 inches) for ‘Clear Madness Mix’, and 5.7 cm (2.2 inches) for ‘Waterfall Madness Mix’. After sowing, the first bloom opened in 53 days for ‘Clear Madness Mix’ and 61 days for ‘Waterfall Madness Mix’. The overall rating for foliage/flower quality was 5.1 for ‘Clear Madness Mix’ and 5.4 for ‘Waterfall Madness Mix’, and the overall pest rating was 6.2 for ‘Clear Madness Mix’ and 6.0 for ‘Waterfall Madness Mix’. The overall performance rating was 5.6 for ‘Clear Madness Mix’ and 5.7 for ‘Waterfall Madness Mix’. ‘Waterfall Madness Mix’ was selected best-of-class.

Single pink class. ‘Celebrity Chiffon Morn Improved’ had a flower diameter of 6.3 cm (2.5 inches), and the first bloom opened 55 days after sowing. The overall rating for foliage/flower quality was 5.0, and the overall pest rating was 6.2. The overall performance rating was 5.6. ‘Celebrity Chiffon Morn Improved’ is uncontested best-of-class.

Single purple, red-violet (dark) class. Flower diameters for ‘Celebrity Burgundy Improved’ and ‘Magenta Madness’ were both 5.5 cm (2.2 inches). After sowing, the first bloom opened in 55 days for ‘Celebrity Burgundy Improved’ and 61 days for ‘Magenta Madness’. The overall rating for foliage/flower quality was 5.2 for ‘Celebrity Burgundy Improved’ and 5.1 for ‘Magenta Madness’, and the overall pest rating was 5.6 for 'Celebrity Burgundy Improved’ and 6.0 for ‘Magenta Madness’. The overall performance rating was 5.4 for ‘Celebrity Burgundy Improved’ and 5.5 for ‘Magenta Madness’. ‘Magenta Madness’ was selected best-of-class.

Single rose class. ‘Celebrity Rose’ had a flower diameter of 5.2 cm (2.0 inches), and the first bloom opened 53 days after sowing. The overall rating for foliage/flower quality was 4.9, and the overall pest rating was 6.1. The overall performance rating was 5.5. ‘Celebrity Rose’ is uncontested best-of-class.

Single white class. ‘Celebrity White’ had a flower diameter of 6.0 cm (2.4 inches), and the first bloom opened 68 days after sowing. The overall rating for foliage/flower quality was 4.8, and the overall pest rating was 5.4. The overall performance rating was 5.0. ‘Celebrity White’ is uncontested best-of-class.

Grandifloras

Single blue (dark) class. ‘Storm Blue’ had a flower diameter of 6.3 cm (2.5 inches), and the first bloom opened 62 days after sowing. The overall rating for foliage/flower quality was 5.3, and the overall pest rating was 6.1. The overall performance rating was 5.7. ‘Storm Blue’ is uncontested best-of-class.

Single mix class. ‘Stars and Stripes Mix’ had a flower diameter of 7.7 cm (2.5 inches), and the first bloom opened 62 days after sowing. The overall rating for foliage/flower quality was 4.3, and the overall pest rating was 5.4. The overall performance rating was 4.9. ‘Stars and Stripes Mix’ is uncontested best-of-class.

Single pink class. Flower diameter was 6.7 cm (2.6 inches) for ‘Aladdin Pink Morn’, 6.0 cm (2.4 inches) for ‘Storm Pink’ and 6.2 cm (2.4 inches) for ‘Storm Pink Morn’. After sowing, the first bloom opened in 58 days for ‘Aladdin Pink Morn’ and ‘Storm Pink Morn’, and in 59 days for ‘Storm Pink’. The overall rating for foliage/flower quality was 4.5 for ‘Aladdin Pink Morn’, 4.4 for ‘Storm Pink’, 4.7 for ‘Storm Pink Morn’, and the overall pest rating was 5.8 for ‘Aladdin Pink Morn’, 5.5 for ‘Storm Pink’, and 5.9 for ‘Storm Pink Morn’. The overall performance rating was 5.1 for ‘Aladdin Pink Morn’, 4.9 for ‘Storm Pink’, and 5.3 for ‘Storm Pink Morn’. ‘Storm Pink Morn’ was selected best-of-class.

Single purple, blue-violet (light) class. ‘Storm Lavender’ had a flower diameter of 6.2 cm (2.4 inches), and the first bloom opened 61 days after sowing. The overall rating for foliage/flower quality was 5.1, and the overall pest rating was 6.0. The overall performance rating was 5.5. ‘Storm Lavender’ is uncontested best-of-class.

Single purple, blue-violet (light)/red class. ‘Aladdin Strawberry Ice’ had a flower diameter of 7.0 cm (2.8 inches), and the first bloom opened 65 days after sowing. The overall rating for foliage/flower quality was 4.5, and the overall pest rating was 5.7. The overall performance rating was 5.1. ‘Aladdin Strawberry Ice’ is uncontested best-of-class.

Single purple, red-violet (dark) class. Flower diameter was 6.7 cm (2.6 inches) for ‘Aladdin Burgundy Improved’, and 6.9 cm (2.7 inches) for ‘Storm Violet’. After sowing, the first bloom opened in 64 days for ‘Aladdin Burgundy Improved and 60 days for ‘Storm Violet’. The overall rating for foliage/flower quality was 4.0 for ‘Aladdin Burgundy Improved’ and 5.0 for ‘Storm Violet’. The overall pest rating was 6.1 for ‘Aladdin Burgundy Improved’ and 6.2 ‘Storm Violet’. The overall performance rating was 5.1 for ‘Aladdin Burgundy Improved’ and 5.6 for ‘Storm Violet’. ‘Storm Violet’ was selected best-of-class.

Single red class. Flower diameter was 6.5 cm (2.6 inches) for ‘Aladdin Cherry Improved’, 6.7 cm (2.6 inches) for ‘Aladdin Orange’, 6.6 cm (2.6 inches) for ‘Storm Red’ and 7.7 cm (3.0 inches) for ‘Ultra Red’. After sowing, the first bloom opened in 60 days for ‘Aladdin Cherry Improved’, 62 days for ‘Aladdin Orange’, 59 days for ‘Storm Red’ and 62 days for ‘Ultra Red’. The overall rating for foliage/flower quality was 4.5 for ‘Aladdin Cherry Improved’, 4.2 for ‘Aladdin Orange’, 3.6 for ‘Storm Red’ and 3.9 d for ‘Ultra Red’. The overall pest rating was 5.8 for ‘Aladdin Cherry Improved’, 5.6 for ‘Aladdin Orange’ and ‘Storm Red’, and 5.5 for ‘Ultra Red’. The overall performance rating was 5.1 for ‘Aladdin Cherry Improved’, 4.9 for ‘Aladdin Orange’, 4.6 for ‘Storm Red’ and 4.7 days for ‘Ultra Red’. ‘Aladdin Cherry Improved’ was selected best-of-class.

Single salmon class. Flower diameter was 7.6 cm (3.0 inches) for ‘Bravo Salmon Improved’, 6.0 cm (2.4 inches) for ‘Storm Salmon’ and 7.4 cm (2.9 inches) for ‘Ultra Salmon’. After sowing, the first bloom opened in 60 days for ‘Bravo Salmon Improved, 58 days for ‘Storm Salmon’ and 64 days for ‘Ultra Salmon’. The overall rating for foliage/flower quality was 4.8 for ‘Bravo Salmon Improved’, 4.0 for ‘Storm Salmon’ and 5.1 for ‘Ultra Salmon’. The overall pest rating was 5.9 for ‘Bravo Salmon Improved’, 6.2 for ‘Storm Salmon’ and 6.3 for ‘Ultra Salmon’. The overall performance rating was 5.3 for ‘Bravo Salmon Improved’, 5.1 for ‘Storm Salmon’ and 5.7 for ‘Ultra Salmon’. ‘Ultra Salmon’ was selected best-of-class.

Single white class. Flower diameter was 7.5 cm (3.0 inches) for ‘Aladdin White’ and ‘Storm White’ and 7.4 cm (2.9 inches) for ‘Ultra White’. After sowing, the first bloom opened in 65 days for ‘Aladdin White, 63 days for ‘Storm White’ and 60 days for ‘Ultra White’. The overall rating for foliage/flower quality was 3.9 for ‘Aladdin White’, 4.5 for ‘Storm White’ and 3.8 for ‘Ultra White’, and the overall pest rating was 5.3 for ‘Aladdin White’, 5.5 for ‘Storm White’ and 5.8 for ‘Ultra White’. The overall performance rating was 4.6 for ‘Aladdin White’, 5.0 for ‘Storm White’ and 4.8 for ‘Ultra White’. ‘Storm White’ was selected best-of-class.

Single mix class. ‘Fantasy Mix’ had a flower diameter of 3.8 cm (1.5 inches), and the first bloom opened 55 days after sowing. The overall rating for foliage/flower quality was 4.8, and the overall pest rating was 6.5. The overall performance rating was 5.7. ‘Fantasy Mix’ is uncontested best-of-class.

Single purple, blue violet (light) class. ‘Fantasy Light Lavender’ had a flower diameter of 4.0 cm (1.6 inches), and the first bloom opened 56 days after sowing. The overall rating for foliage/flower quality was 5.4, and the overall pest rating was 6.5. The overall performance rating was 6.0. ‘Fantasy Light Lavender’ is uncontested best-of-class.

Multifloras

Single mix class. ‘Old Glory Mix’ had a flower diameter of 5.7 cm (2.2 inches), and the first bloom opened 59 days after sowing. The overall rating for foliage/flower quality was 4.3, and the overall pest rating was 6.4. The overall performance rating was 5.3. ‘Old Glory Mix’ is uncontested best-of-class.

Single pink class. ‘Hurrah Pink Chiffon’ had a flower diameter of 5.6 cm (2.2 inches), and the first bloom opened 55 days after sowing. The overall rating for foliage/flower quality was 5.0, and the overall pest rating was 6.5. The overall performance rating was 5.7. ‘Hurrah Pink Chiffon’ is uncontested best-of-class.

Single purple/white class. ‘Primetime Violet Star’ had a flower diameter of 5.5 cm (2.2 inches), and the first bloom opened 59 days after sowing. The overall rating for foliage/flower quality was 4.8, and the overall pest rating was 6.5. The overall performance rating was 5.6. ‘Primetime Violet Star’ is uncontested best-of-class.

Single red/white class. ‘Symphony Red Picotee’ had a flower diameter of 5.3 cm (2.1 inches), and the first bloom opened 53 days after sowing. The overall rating for foliage/flower quality was 4.3, and the overall pest rating was 6.6. The overall performance rating was 5.4. ‘Symphony Red Picotee’ is uncontested best-of-class.

Single rose class. ‘Symphony Rose’ had a flower diameter of 5.7 cm (2.2 inches), and the first bloom opened 51 days after sowing. The overall rating for foliage/flower quality was 5.5, and the overall pest rating was 5.8. The overall performance rating was 5.7. ‘Symphony Rose’ is uncontested best-of-class.

Single rose/white class. ‘Symphony Rose Picotee’ had a flower diameter of 5.3 cm (2.1 inches), and the first bloom opened 53 days after sowing. The overall rating for foliage/flower quality was 3.9, and the overall pest rating was 6.2. The overall performance rating was 5.0. ‘Symphony Rose Picotee’ is uncontested best-of-class.

Single salmon (dark) class. ‘Hurrah Summer’ had a flower diameter of 5.9 cm (2.3 inches), and the first bloom opened 56 days after sowing. The overall rating for foliage/flower quality was 3.5, and the overall pest rating was 6.3. The overall performance rating was 4.9. ‘Hurrah Summer’ is uncontested best-of-class.

Spreading Types

Single blue (dark) class. Flower diameter was 5.3 cm (2.1 inches) for ‘Explorer Blue’, and ‘Ramblin' Nu Blue’, and 5.0 cm (2.0 inches) for ‘Wave Blue’. After sowing, the first bloom opened in 68 days for ‘Explorer Blue, and 53 days for ‘Ramblin' Nu Blue’ (no data for ‘Wave Blue’). The overall rating for foliage/flower quality was 4.9 for ‘Explorer Blue’, 5.0 for ‘Ramblin' Nu Blue’ and 5.4 for ‘Wave Blue’, and the overall pest rating was 6.2 for ‘Explorer Blue’and ‘Ramblin' Nu Blue’, and 6.5 for ‘Wave Blue’. The overall performance rating was 5.5 for ‘Explorer Blue’, 5.6 for ‘Ramblin' Nu Blue’ and 6.0 for ‘Wave Blue’. ‘Wave Blue’ was selected best-of-class.

Single pink class. Flower diameter was 6.1 cm (2.4 inches) for ‘Easy Wave Pink’, 5.2 cm (2.0 inches) for ‘Explorer Rose Pink’, 5.6 cm (2.2 inches) for ‘Explorer Pink’ and ‘Ramblin' Shades O' Pink’ and 5.1 cm (2.0 inches) for ‘Wave Pink Improved’. After sowing, the first bloom opened in 62 days for ‘Easy Wave Pink’, 61 days for ‘Explorer Rose Pink’ and Ramblin' Shades O' Pink’, 56 days for ‘Explorer Pink’ and 75 days for ‘Wave Pink Improved’. The overall rating for foliage/flower quality was 5.5 for ‘Easy Wave Pink’, 5.9 for ‘Explorer Rose Pink’ and ‘Wave Pink Improved’, 4.5 for ‘Explorer Pink’ and ‘Ramblin' Shades O' Pink’. The overall pest rating was 5.6 for ‘Easy Wave Pink’, 6.3 for ‘Explorer Rose Pink’ 6.5 for ‘Explorer Pink’, 6.4 for ‘Ramblin' Shades O' Pink’ and 6.7 for ‘Wave Pink Improved’. The overall performance rating was 5.6 for ‘Easy Wave Pink’, 6.1 for ‘Explorer Rose Pink’ 6.0 for ‘Explorer Pink’, 5.8 for ‘Ramblin' Shades O' Pink’ and 6.3 for ‘Wave Pink Improved’. ‘Wave Pink Improved’ was selected best-of-class.

Single pink (light) class. ‘Easy Wave Shell Pink’ had a flower diameter of 5.6 cm (2.2 inches), and the first bloom opened 54 days after sowing. The overall rating for foliage/flower quality was 6.1, and the overall pest rating was 6.5. The overall performance rating was 6.3. ‘Easy Wave Shell Pink’ is uncontested best-of-class.

Single purple, blue-violet (dark) class. Flower diameter was 5.6 cm (2.2 inches) for ‘Avalanche Lavender’ and 5.2 cm (2.0 inches) for ‘Explorer Lavender’. After sowing, the first bloom opened in 65 days for ‘Avalanche Lavender’ and 64 days for ‘Explorer Lavender’. The overall rating for foliage/flower quality was 5.6 for ‘Avalanche Lavender’ and 5.5 for ‘Explorer Lavender’. The overall pest rating was 6.2 for ‘Avalanche Lavender’ and 6.3 for ‘Explorer Lavender’. The overall performance rating was 5.9 for ‘Avalanche Lavender’ and ‘Explorer Lavender’. ‘Avalanche Lavender’ was selected best-of-class, based on the overall rating for foliage/flower quality.

Single purple, blue-violet (light) class. ‘Avalanche Lilac Improved’ had a flower diameter of 6.1 cm (2.4 inches), and the first bloom opened 62 days after sowing. The overall rating for foliage/flower quality was 5.6, and the overall pest rating was 6.7. The overall performance rating was 6.1. ‘Avalanche Lilac Improved’ is uncontested best-of-class.

Single purple, red-violet (very dark) class. Flower diameter was 4.8 cm (1.9 inches) for ‘Explorer Magenta’ and 5.7 cm (2.2 inches) for ‘Opera Deep Purple’. After sowing, the first bloom opened in 78 days for ‘Explorer Magenta and 68 days for ‘Opera Deep Purple’. The overall rating for foliage/flower quality was 5.3 for ‘Explorer Magenta’ and 5.6 for ‘Opera Deep Purple’, and the overall pest rating was 6.4 for ‘Explorer Magenta’ and 6.3 for ‘Opera Deep Purple’. The overall performance rating was 5.8 for ‘Explorer Magenta’ and 5.9 for ‘Opera Deep Purple’. ‘Opera Deep Purple’ was selected best-of-class.

Single purple, red-violet (dark) class. Flower diameter was 5.7 cm (2.2 inches) for ‘Explorer Purple’ and 5.4 cm (2.1 inches) for ‘Opera Light Purple’. After sowing, the first bloom opened in 64 days for ‘Explorer Purple’ and 71 days for ‘Opera Light Purple’. The overall rating for foliage/flower quality was 5.8 for ‘Explorer Purple’ and ‘Opera Light Purple’. The overall pest rating was 6.2 for ‘Explorer Purple’ and 6.4 for ‘Opera Light Purple’. The overall performance rating was 6.0 for ‘Explorer Purple’ and 6.1 for ‘Opera Light Purple’. ‘Opera Light Purple’ was selected best-of-class.

Single red class. Flower diameter was 5.8 cm (2.3 inches) for ‘Avalanche Cherry’ and ‘Avalanche Tropical Red’, 4.6 cm (1.8 inches) for ‘Avalanche Red’, and 5.6 cm (2.2 inches) for ‘Easy Wave Cherry’. After sowing, the first bloom opened in 65 days for ‘Avalanche Cherry, 61 days for ‘Avalanche Red’, 76 days for ‘Avalanche Tropical Red’ and 57 days for ‘Easy Wave Cherry’. The overall rating for foliage/flower quality was 5.4 for ‘Avalanche Cherry’ and ‘Easy Wave Cherry’, and 4.9 for ‘Avalanche Red’ and ‘Avalanche Tropical Red’. Overall pest rating was 6.1 for ‘Avalanche Cherry’, 6.3 for ‘Avalanche Red’ 6.2 for ‘Avalanche Tropical Red’ and ‘Easy Wave Cherry’. The overall performance rating was 5.7 for ‘Avalanche Cherry’, 5.5 for ‘Avalanche Red’ and ‘Avalanche Tropical Red’, and 5.8 for ‘Easy Wave Cherry’. ‘Easy Wave Cherry’ was selected best-of-class.

Single rose class. Flower diameter was 5.1 cm (2.0 inches) for ‘Avalanche Rose’ and ‘Opera Deep Rose’, 5.2 cm (2.0 inches) for ‘Explorer Rose’, and 4.7 cm (1.9 inches) for ‘Ramblin' Neon Rose’. After sowing, the first bloom opened in 62 days for ‘Avalanche Rose’, 67 days for ‘Explorer Rose’, 52 days for ‘Opera Deep Rose’ and 68 days for ‘Ramblin' Neon Rose’. The overall rating for foliage/flower quality was 4.9 for ‘Avalanche Rose’, 6.0 for ‘Explorer Rose’, 5.8 for ‘Opera Deep Rose’ and 4.7 for ‘Ramblin' Neon Rose’. Overall pest rating was 6.3 for ‘Avalanche Rose’ and ‘Opera Deep Rose’, 6.2 for ‘Explorer Rose’ and 6.0 for ‘Ramblin' Neon Rose’. The overall performance rating was 5.6 for ‘Avalanche Rose’, 6.1 for ‘Explorer Rose’, 6.0 for ‘Opera Deep Rose’ and 5.4 for ‘Ramblin' Neon Rose’. ‘Explorer Rose’ was selected best-of-class.

Single salmon (dark) class. ‘Ramblin' Deep Salmon’ had a flower diameter of 5.0 cm (2.0 inches), and the first bloom opened 61 days after sowing. The overall rating for foliage/flower quality was 5.2, and the overall pest rating was 6.3. The overall performance rating was 5.7. ‘Ramblin' Deep Salmon’ is uncontested best-of-class.

Single salmon (light) class. Flower diameter was 4.8 cm (1.9 inches) for ‘Avalanche Salmon’ and 5.4 cm (2.1 inches) for ‘Ramblin' Peach Glo’. After sowing, the first bloom opened in 61 days for ‘Avalanche Salmon’ and 58 days for ‘Ramblin' Peach Glo’. The overall rating for foliage/flower quality was 4.6 for ‘Avalanche Salmon’ and 5.5 for ‘Ramblin' Peach Glo’. The overall pest rating was 6.6 for ‘Avalanche Salmon’ and 6.5 for ‘Ramblin' Peach Glo’. The overall performance rating was 5.6 for ‘Avalanche Salmon’ and 6.0 for ‘Ramblin' Peach Glo’. ‘Ramblin' Peach Glo’ was selected best-of-class.

Single white class. Flower diameter was 5.5 cm (2.2 inches) for ‘Avalanche White’ and 6.0 cm (2.4 inches) for ‘Explorer White’. After sowing, the first bloom opened in 68 days for ‘Avalanche White” and 70 days for ‘Explorer White’. The overall rating for foliage/flower quality was 5.4 for ‘Avalanche White’ and 5.1 for ‘Explorer White’. The overall pest rating was 6.0 for ‘Avalanche White’ and 6.3 for ‘Explorer White’. The overall performance rating was 5.7 for ‘Avalanche White’ and ‘Explorer White’. ‘Avalanche White’ was selected best-of-class, based on overall rating for foliage/flower quality.

Tall - single purple, blue-violet (light) class. ‘Ramblin' Misty Lilac’ had a flower diameter of 6.0 cm (2.4 inches), and the first bloom opened 57 days after sowing. The overall rating for foliage/flower quality was 5.5, and the overall pest rating was 6.4. The overall performance rating was 5.9. ‘Ramblin' Misty Lilac’ is uncontested best-of-class.

Tall - single purple, red-violet (dark) class. ‘Ramblin' Burgundy Chrome’ had a flower diameter of 5.1 cm (2.0 inches), and the first bloom opened 65 days after sowing. The overall rating for foliage/flower quality was 5.6, and the overall pest rating was 5.8. The overall performance rating was 5.7. ‘Ramblin' Burgundy Chrome’ is uncontested best-of-class.

Tall - single purple, red-violet (very dark) class. ‘Kahuna Violet’ had a flower diameter of 4.5 cm (1.8 inches), and the first bloom opened 53 days after sowing. The overall rating for foliage/flower quality was 6.5, and the overall pest rating was 6.2. The overall performance rating was 6.3. ‘Kahuna Violet’ is uncontested best-of-class.

Tall - single white class. ‘Kahuna White’ had a flower diameter of 6.0 cm (2.4 inches), and the first bloom opened 71 days after sowing. The overall rating for foliage/flower quality was 6.0, and the overall pest rating was 6.4. The overall performance rating was 6.2. ‘Kahuna White’ is uncontested best-of-class.

Conclusions and Comments

Overall Performance and Best of Class Cultivars

While early or late season performance, a particular plant height, or shade of the same color may be a selection criteria outweighing seasonal performance, the combined foliage and flower ratings represent an overall view of performance for each cultivar in its class over the entire season. We consider cultivars with an adjusted overall performance rating > 6.0 as outstanding, 5.5– 5.9 as very good performers, 5.4 – 5.0 as good and 4.0 – 4.9 as fair. This is a summary of cultivar selections listed by performance and class order, with best of class indicated with an asterisk (*) after the cultivar name:

Outstanding cultivars (> 6.0) were: [Millifloras] ‘Fantasy Light Lavender’* [single purple, blue violet (light) class]; [Spreading Types] ‘Wave Blue’* [single blue (dark) class]; ‘Explorer Rose Pink’, ‘Explorer Pink’ and ‘Wave Pink Improved’* (single pink class); ‘Easy Wave Shell Pink’* [single pink (light) class]; ‘Avalanche Lilac Improved’* [single purple, blue-violet (light) class]; ‘Explorer Purple’ [single purple, red-violet (dark) class]; ‘Opera Light Purple’* [single purple, red-violet (dark) class]; ‘Explorer Magenta’* [single purple, red-violet (very dark) class]; ‘Explorer Rose’* and ‘Opera Deep Rose ‘ (single rose class); ‘Ramblin' Peach Glo’* [single salmon (light) class]; ‘Kahuna Violet’* [tall - Single purple, red-violet (very dark) class]; and ‘Kahuna White’* [tall - Single white class].

Very Good cultivars (5.5-5.9) were: [Floribundas] ‘Celebrity Mid Blue’* (single blue class); ‘Clear Madness Mix’ and ‘Waterfall Madness Mix’* (single mix class); ‘Celebrity Chiffon Morn Improved’* (single pink class); ‘Magenta Madness’* [single purple, red-violet (dark) class]; ‘Celebrity Rose’* (single rose class); [Grandifloras] ‘Storm Blue’* [single blue (dark) class]; ‘Storm Lavender’* [single purple, blue-violet (light) class); ‘Storm Violet’* (single purple, red-violet (dark) class]; ‘Ultra Salmon’ (single salmon class); [Millifloras] ‘Fantasy Mix’* (single mix class); [Multifloras] ‘Hurrah Pink Chiffon’* (single pink class); ‘Primetime Violet Star’* (single purple/white class); ‘Symphony Rose’* (single rose class); [Spreading Types] ‘Explorer Blue’ and ‘Ramblin' Nu Blue’ [single blue (dark) class]; ‘Easy Wave Pink’ and ‘Ramblin' Shades O' Pink’ (single pink class); ‘Avalanche Lavender’ and ‘Explorer Lavender’* [single purple, blue-violet (dark) class]; ‘Opera Deep Purple’ [single purple, red-violet (very dark) class]; ‘Avalanche Cherry’, ‘Avalanche Red’, ‘Avalanche Tropical Red’ and ‘Easy Wave Cherry’* (single red class); ‘Avalanche Rose’ (single rose class); ‘Ramblin' Deep Salmon’* [single salmon (dark) class]; ‘Avalanche Salmon’ [single salmon (light) class]; ‘Avalanche White’ and ‘Explorer White’* (single white class); ‘Ramblin' Misty Lilac’* [tall - Single purple, blue-violet (light) class]; and ‘Ramblin' Burgundy Chrome’* [tall - Single purple, red-violet (dark) class].

Good cultivars (5.4-5.0) were: [Floribundas] ‘Celebrity Burgundy Improved’ [single purple, red-violet (dark) class]; ‘Celebrity White’ (single white class); [Grandifloras] ‘Aladdin Pink Morn’ and ‘Storm Pink Morn’ (single pink class); ‘Aladdin Strawberry Ice’ (single purple, blue-violet (light)/red class); ‘Aladdin Burgundy Improved’ [single purple, red-violet (dark) class]; ‘Aladdin Cherry Improved’ (single red class); ‘Bravo Salmon Improved’ and ‘Storm Salmon’ (single salmon class); ‘Storm White’* (single white class); [Multifloras] ‘Old Glory Mix’ (single mix class); ‘Symphony Red Picotee’ (single red/white class); ‘Symphony Rose Picotee’ (single rose/white class); [Spreading Types] ‘Ramblin' Neon Rose’ (single rose class).

Fair cultivars (4.0-4.9) were: [Grandifloras] ‘Stars and Stripes Mix’* (single mix class); ‘Storm Pink’ (single pink class); ‘Aladdin Orange’, ‘Storm Red’ and ‘Ultra Red’ (single red class); ‘Aladdin White’ and ‘Ultra White’ (single white class); ‘Hurrah Summer’* [single salmon (dark) class].

Pest evaluations in the unsprayed field

Plant pests – arthropods. Symptoms were relatively minor, and the foliage and flower quality affected by these pests remained generally good to excellent all season. Symptoms of chewing insects were seen and beet army worms [Spodoptera exigua (Huebner) (Insecta: Lepidoptera: Noctuidae] were found associated with this damage. Garden fleahoppers [Halticus bractatus (Say) (Insecta: Hemiptera: Miridae)], flower thrips [Frankliniella bispinosa (Morgan)], leafminer [Liriomyza trifolii (Burgess) (Insecta: Diptera: Agromyzidae)] and twospotted spider mite [Tetranychus urticae Koch (Arachnida: Acari: Tetranychidae)] were detected.

Plant pests – disease. Foliar and flower disease pathogens were isolated and identified by a plant pathologist. Chorynespora sp. and Alternaria sp. occurred on petunia foliage. Sclerotinia fuckeliana (de Gary) Fuckel, (conidial state: Botrytis cinerea Pers. ex Fr.) and Choanephora sp. were isolated in mid May and early June, respectively. S. fuckeliana is found more often in climates that are humid temperate or subtropical (Ellis & Waller). The affects of foliar disease symptoms (blights and spots) affecting plant foliage quality were minimal for most cultivars (Tables 3), while flower symptoms became severe for floribundas and grandifloras in early June. The millifloras, multifloras and most of the spreading types remained healthy; however, the spreading red class and half of the rose class had only fair performance in early June, indicating a possible weakness in these classes, relative to the other classes evaluated in this trial (Table 4). Plant death was very minor for petunias and did not seem to be cultivar-related; therefore, it was not factored into the overall performance rating.

Variety Trials Website

This report may be found in the Articles, Papers & Reports link on the variety trials web page [http://vtgcrec.ifas.ufl.edu/index.htm] for viewing, sending a link or printing (PDF format). Digital images and the overall ratings for the spring 2002 petunia cultivars evaluated in this report may be found by following the Recently Completed Trials link (trails home page) to the Current & Recent Trials link. These links and their titles are subject to change in the future, as the web page is modified.

Note

The information in this report is a summary of experimental results and does not provide recommendations for crop production. Where trade names are used, no discrimination is intended or endorsement implied.

Ellis, M. B. and J. M. Walker. 1974. Sclerotinia fuckeliana (Conidial State: Botrytis cinerea), CMI Descriptions of Pathogenic Fungi and Bacteria, No. 432.

Florida Automated Weather Network. 2003. FAWN: Florida Automated Weather Network. 19 June 2003.
http://fawn.ifas.ufl.edu/.

Kelly, R. O., B. Harbaugh and R. Schoellhorn. 2002. Evaluation of Impatiens Cultivars as Bedding Plants – Spring 2001. GCREC Bradenton Res. Rept. BRA 2002-9.

[1] Variety trials coordinator

[2] Associate professor of floriculture

[3] Assistant professor of floriculture

[4] Professor of floriculture