桔梗生長於臺北冬季至初夏(12月~7月),於播種後約140天,莖略抽長時摘心,留2~4側芽,待芽長約3~5cm時,予矮化劑處理。矮化效果以B-9效果有好,Ancymidol次之,而Cycocel無效。使用濃度因品種而異,品種「山之紫」噴施B-9 2500 ppm即足,匹「櫻之峰」需5000 ppm或2500 ppm噴施2次。Ancymidol的灌施,「山之紫」約0.264mg/盆一次,而「霧之峰」則爲0.5mg/盆2次或1.0mg/盆2次。 矮化劑的處理,主要是抑制節間的伸長,對開花日期、花朵壽命無明顯影響。摘心後植株愈後期處理矮化劑,則小花梗的伸長花瓣長度,受抑制愈明顯。處理植株花期可持續2個月,爲極具發展潛力。不可多得的夏季盆花。
Lisianthus (lisianthus resellianus) grown in Taipei from winter through summer for pot flowers were studied. Plants were pinched at bolting about 140 days after sowing. Growth retardants were used when lateral shoots came out about 3~5cm in length. Cycocel exhibited no effect on height control for pot production, 2500ppm of B-S was suitable concentration for blue cultivar, while 5000ppm or 2500ppm sprayed for twice wan proper for pink cultivar. The optimal concentrations of soil drenched Ancymidol to blue cultivar and white cultivar were 0.264mg/pot and 0.5mg/pot or 1.0mg /pot for twice, respectively. The results showed that Ancymidol and B-S only inhibited internode elongation, but did not affect on either flowering time or flower quality. However, if spray too late after pinching, the length of pedicel and petals were shorter than control.