花海

南華杜鵑 - 攝於2012年4月

《香港物種探索》第 23 期（ 2015 年 4 月 ）
http://www.afcd.gov.hk/tc_chi/conservation/hkbiodiversity/newsletters/newsletters.html
雖然並不包括南華杜鵑，但就羊角杜鵑、香港杜鵑及毛葉杜鵑盛開與否，有以下觀察
"A pattern of alternate-year flowering was recorded for the
rhododendrons in Ma On Shan from 2009 to 2012. The likelihood of
flowering and the number of flowers were higher when there had been a
dry growing season in the previous year and after a winter with a
short photoperiod. Mass flowering might be the plant's response to
limited resources under stressed conditions."