The photoperiodic responses were determined for the following species: Abutilon hybrid 'Apricot', Diascia hybrid Way Fields', Evolvulus glomeratus'B\ue Daze', Orthosiphonstamineus'Lmntief, Portulaca oleraceae'Apricot', Scaevolaaemula 'Fancy Fan Falls', Sutera cordata 'Mauve Mist' and'Snowflake', Tabernamontana coronaria'Double', and Tibouchina'Spanish Shaw'. Each plant species was grown at8-,10-, 12-, 14-, and 16-h photoperiods. Photoperiods were provided by delivering 8 hofsunlight, then pulling black cloth and providing day length extension with incandescent bulbs. Air temperatures were monitored under each black cloth. Data collected included time toflower, number offlowers, and vegetative character istics. Diascia, Syfe/a'MauveMist'and'Snowflake', Tabemamontana,ar\6 Tibouchina were day neutral with regard toflowering; i.e., nodifference indays tovisible bud or days toanthesis in response tophotoperiod was observed. Portulacaand Scaevola increased in bud and flower number as photoperiod increased from 8to16h, per forming similar to quantitative long-day plants. There was nodifference intime to flower for Portulaca; however, 70% more flowers were produced under the 16-h photoperiod, compared tothe 8-hphotoperiod. Scaevola had 26% more flowers under the 16-h than 8-hphotoperiod. Abutilon, Evolvulus ,and Orthosiphon per formed as quantitative short-day plants. Days tovisible bud and days toanthesis increased asphotoperiod increased for Evolvulusand Orthosiphon, and Abutilon had decreased flower number asphotoperiod increased. Although Abutilon had no difference in time to flower, there was a43% increase in flowers on plants underthe 8-hphotoperiod vs. 16-h photoperiod. Evolvulussetvisible bud and reached an thesis 10days earlier under 8-h photoperiod than 16-h. Orthosiphon reached vis ible bud 32days earlier under an 8-h photoperiod than a16-h photoperiod.
Keywords: Hybrid 'Apricot short-day plants Long-day plants black cloth