Hibiscus is native to various places along the Pacific rim, including southern China. But Dutch cultivars of these hibiscus species do not bloom in the summer in Japan. Consequently, Hanakongou president Narimitsu Ochiai provided some European species and asked Chu to conduct research on them in Taiwan. Unexpectedly, Chu grew them for three years without any success at bearing seeds.
又稱「扶桑花」的朱槿，原產於中國南方等環太平洋地區，而荷蘭培育出的朱槿在日本夏天不開花，於是日本華金剛株式會社社長落合成光提供歐洲種原，請朱建鏞在台灣做研究。