ISHS Acta Horticulturae 272: Symposium on Bedding and Pot Plant Culture
USE OF GROWTH RETARDANTS ON SATIN FLOWER, GODETIA, FOR POT PLANT PRODUCTION |
| Authors: | Robert G. Anderson, G. Hartley |
| Abstract:
Satin flower (Clarkia amoena subsp. whitneyi; syn. Godetia whitneyi; Onagraceae) is a cool temperature cutflower that produces a number of 6–8 cm, 4-petaled flowers at the tips of 0.5 to 1.0 m tall stems. Growth retardants - chlormequat, daminozide, ancymidol, paclobutrazol, uniconazole - were applied as foliar sprays and soil drenches at various concentrations and times of application to determine if plant height could be controlled for pot plant production. During the fall and winter (ambient light conditions), three soil applications of paclobutrazol at 11 ppm and two or three soil applications of uniconazole at 11 ppm reduced plant height to a 20–30 cm. One or two soil applications of uniconazole at 16.5 ppm gave the most acceptable height control for 'Grace Rose Pink' while 'Grace Shell Pink' required three or four applications for equal height control. Flowering was delayed 2–4 weeks with all treatments but flower size appeared normal. In a separate trial, plants were grown under 24 hr supplemental lighting (100 μ mol m-2s-1). Two foliar applications of daminozide at 5000 ppm, two soil applications of paclobutrazol at 20 ppm or two soil applications of uniconazole at 15 ppm significantly reduced the plant height five weeks after transplanting. However all plants eventually overcame the chemical treatment to become approximately equal in height to untreated plants at flowering; flowering was delayed one to two weeks on treated plants. Plants flowered in 8–9 weeks under supplemental lighting whereas under fall and winter ambient light conditions, flowering occurred in 15–18 weeks. | |
Download Adobe Acrobat Reader (free software to read PDF files) | |
