Change in photoperiod had no affect on flower initiation of Sakata F-1 hybrid E, grandiflorum; however, plant flower buds developed faster, had increased stem length, greater number of bud nodes, and more plant fresh and dry weight when exposed to day growing temperature and relative humidities of 22° C and 70%, compared to 17° C and 30-50% respectively. Sakata plants grown in volcanic scoria, gravel, and idealite had better growth and production than those in soil medium. The removal of terminal shoots at the fourth, fifth or sixth leaf pairs above the base, had no effect on growth, however, the removal of the growing tip only, reduced the flowering time by 10 days. The Weddle hybrid of E. grandiflorum was more productive and had larger stems than the Sakata hybrids. Both hybrids had two definite flowering cycles per year, one from May through June, and a second from August to mid-October. The vase life of both hybrids ranged from 8 to 18 days, but was not increased by preservative addition of 8-hydroxyquinoline citrate, (8-HQC), plus sugar. E. grandiflorum was attacked by red spider mite (Tetranychus urticae) and white fly (Trialeurades vaporariorurn) and was highly susceptible to Rhizoctonia solani and Fusarium spp.

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