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The effects of concentration and method of application of uniconazole on growth and flowering of Scaevola aemula R. Br. `New Wonder', `Mini Pink Fan', `Purple Fan', and `Royal Fan', Scaevola albida (Sm.) Druce. `White Fan', and Scaevola striata `Colonial Fan' were studied, as was the efficacy of four other growth retardants on S. aemula `New Wonder'. Variables measured included plant width, flower stem number, flower stem length, flower number per stem, flower number per cm stem length, and days to flower. Uniconazole (1.0 mg·L<sup>–1</sup>) applied as a medium drench to S. aemula `New Wonder' reduced plant width and flower stem length without affecting flower stem number or time to flower. Flower number per stem and number of flowers per cm of stem length were increased, resulting in attractive, compact clusters of flowers. Paclobutrazol medium drench at 4.0 mg·L^–1 gave similar results. Daminozide and ethephon sprays reduced plant width; however, flower number was reduced and ethephon delayed flowering. Ancymidol did not affect the parameters measured. When uniconazole drenches were applied to the other cultivars, plant width and flower stem length in all cultivars except `White Fan' decreased as rate increased. Spray applications reduced plant width of all cultivars except `Mini Pink Fan'. Flower stem length was not affected in any cultivar. Flowering habit was improved more in S. aemula `New Wonder', `Purple Fan', and `Royal Fan' than in the other cultivars. Chemical names used: α-cyclopropyl-α-(4-methoxyphenyl)-5-pyrimidinemethanol (ancymidol); butanedioic acid mono (2,2-dimethylhydrazide) (daminozide); (2-chloroethyl)phosphonic acid (ethephon); β-[(4-chlorophenyl)methyl]-α-(1,1-dimethylethyl)-1H-1,2,4-triazole-1-ethanol (paclobutrazol); (E)-(s)-1-(4-chlorophenyl)-4,4-dimethy-2-(1,2,4-triazol-1-yl)-pent-1-ene-3-ol (uniconazole).

The photoperiodic responses were determined for the following species: Bacopa speciosa `Snowflake', Bidens ferulifolium, Brachycome multifida `Crystal Falls', Helichrysum bracteatum'Golden Beauty', Lysimachia procumbens (Golden Globes), Pentas lanceolata `Starburst', Scaevola aemula `New Blue Wonder', Streptocarpella hybrid `Concord Blue', and Streptosolen jamesonii (Orange Browallia). Each plant species was grown at 8-, 10-, 12-, 14-, and 16-hour photoperiods. Photoperiods were provided by delivering 8 hours sunlight, then pulling black cloth and providing daylength extension with incandescent bulbs. Bacopa speciosa `Snowflake', Bidens ferulifolium, Brachycome multifida `Crystal Falls', Helichrysum bracteatum `Golden Beauty', Scaevola aemula `New Blue Wonder', and Streptocarpella hybrid `Blue Concord' were day neutral, i.e., no difference in days to visible bud or days to anthesis in response to photoperiod were observed. Pentas lanceolata `Starburst' and Lysimachia procumbens (Golden Globes) were quantitative long day plants, i.e., days to anthesis decreased as daylength increased. No difference in days to visible bud, number of lateral shoots, number of nodes, or internode length were observed for Pentas lanceolata `Starburst'; however, days to anthesis for 14- and 16-hour photoperiods occurred 9 days earlier than 8-hour photoperiods. Days to visible bud for Lysimachia procumbens (Golden Globes) occurred 7 days earlier and days to anthesis was 9 days earlier under 14- and 16-hour photoperiods than 8-hour photoperiods. By week 8, only one flower per plant developed in the 8-hour photoperiod while 11 flowers per plant developed in the 14-hour photoperiod. Streptosolen jamesonii (Orange Browallia) was a qualitative short day plant. There was no difference in the days to anthesis between 8- and 10-hour daylength, each averaging 36 days from start of photoperiod treatment. Plants under 12- to 16-hour photoperiods did not flower.

The photoperiodic responses were determined for the following species: Abutilon hybrid `Apricot', Diascia hybrid `Ruby Fields', Evolvulus glomeratus `Blue Daze', Orthosiphon stamineus `Lavender', Portulaca oleraceae `Apricot', Scaevola aemula `Fancy Fan Falls', Sutera cordata `Mauve Mist' and `Snowflake', Tabernamontana coronaria `Double', and Tibouchina `Spanish Shaw'. Each plant species was grown at 8-, 10-, 12-, 14-, and 16-h photoperiods. Photoperiods were provided by delivering 8 h of sunlight, then pulling black cloth and providing daylength extension with incandescent bulbs. Air temperatures were monitored under each black cloth. Data collected included time to flower, number of flowers, and vegetative characteristics. Diascia, Sutera `Mauve Mist' and `Snowflake', Tabernamontana, and Tibouchina were day neutral with regard to flowering; i.e., no difference in days to visible bud or days to anthesis in response to photoperiod was observed. Portulaca and Scaevola increased in bud and flower number as photoperiod increased from 8 to 16 h, performing similar to quantitative long-day plants. There was no difference in time to flower for Portulaca; however, 70% more flowers were produced under the 16-h photoperiod, compared to the 8-h photoperiod. Scaevola had 26% more flowers under the 16-h than 8-h photoperiod. Abutilon, Evolvulus,and Orthosiphon performed as quantitative short-day plants. Days to visible bud and days to anthesis increased as photoperiod increased for Evolvulus and Orthosiphon, and Abutilon had decreased flower number as photoperiod increased. Although Abutilon had no difference in time to flower, there was a 43% increase in flowers on plants under the 8-h photoperiod vs. 16-h photoperiod. Evolvulus set visible bud and reached anthesis 10 days earlier under 8-h photoperiod than 16-h. Orthosiphon reached visible bud 32 days earlier under an 8-h photoperiod than a 16-h photoperiod.

The effect of increasing temperatures on the duration of postharvest flower development was determined for three specialty crop species: marguerite (Argyranthemum frutescens Webb ex Schultz-Bip.) `Butterfly' and `Sugar Baby'; swan river daisy (Brachycome hybrid Cass.) `Ultra'; and bacopa (Sutera cordata Roth.) `Snowflake'. Plants were grown in a greenhouse at 18 °C (65 °F) until flowering, and then transferred into a phytotron to determine heat tolerance. Plants were stored for 8 weeks at constant temperatures of 18, 23, 28, and 33 °C (65, 73, 82, and 91 °F) for 2-week intervals. Flower bud and flower number were recorded weekly. Sutera cordata `Snowflake' and B. hybrid `Ultra' had the greatest flower number at the 23 °C temperature, decreasing in the 28 °C environment. Argyranthemum frutescens `Butterfly' and `Sugar Baby' had greatest flower number at 28 °C, but flowers were of lower quality thanat 23 °C. Flower development of all cultivars ceased at 33 °C, at the end of 8 weeks at increasing temperatures, but when plants were returned to the 18 °C production greenhouse, flower development resumed. High temperatures (28 °C) reduce the postharvest performance of S. cordata, B. hybrid, and A. frutescens plants grown in hanging baskets; therefore, these species should be marketed as spring-flowering products since summer performance may be unsatisfactory in warm climates.

The objective was to determine the optimum number of plants and the number of pinches required to market a basket for hanging basket production using alternative floriculture species. The number of plants per pot varied from one to four, and the number of manual pinches per basket ranged from 0 to 2. Several species were evaluated in spring of 1996 and heat tolerance was assessed throughout the summer. Plugs (50–95 plugs per flat) were transplanted into 25-cm hanging baskets in a 22/18°C (venting/night temperature set points) glasshouse. Three to four plants were necessary for Scaevola aemula `Fancy Fan Falls' and Evolvulus glomeratus `Blue Daze' to produce a marketable basket. One plant per pot was sufficient for Abutilon hybrid `Apricot', Portulaca oleraceae `Apricot', and Tibouchina `Spanish Shaw' without sacrificing quality; however, an additional 1 to 3 weeks production time was needed in comparison to the four plants per pot treatment. Abutilon and Portulaca required one pinch, while Tibouchina did not require pinching. All plants × pinch combinations produced quality baskets with Sutera cordata `Mauve Mist' and Diascia hybrid `Ruby Fields'; therefore, production methods should be based on growers' scheduling and cost analysis. Abutilon, Evolvulus, Portulaca, Scaevola, and Tibouchina performed well in hanging baskets throughout the summer. Two species in the trial, Orthosiphon stamineus `Lavender' and Tabernamontana coronaria, displayed upright growth habits and would be best for uses other than hanging basket production.