`V-14 Glory' poinsettias in 15-cm pots were pinched on 24 Sept. and given long days until 8 Oct. Chemical treatments were paclobutrazol drench, paclobutrazol spray, or daminozide/chlormequat (D/C) spray. Time of application was between 8 Oct. and 12 Nov. Heights ranged between 27 and 31 cm. D/C reduced bract size more than paclobutrazol spray, and for both, later treatments had greater affect. Paclobutrazol drench did not have a significant affect.
A second experiment had two cultivars, `Freedom' and `V-14'; three paclobutrazol concentrations, 0.2, 0.3 or 0.4 mg per pot; and three application times, 30 Sept., 14 Oct. or 28 Oct. Treatment on 30 Sept. produced the smallest bracts. The cultivar × concentration interaction was significant with 0.4 mg reducing bract size for `Freedom' but not `V-14'. Treatments on 28 Oct. had less effect on height than the other two dates. `Freedom' were shorter than `V-14'. and higher concentrations had more effect on `Freedom' than `V-14'.
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