The country has a regulation to residential illumination : the window takes consecutive time completely south do not illuminate hour or1 great cold 2 hours day under solstitial day .

国家对住宅光照有规定：南窗满照连续时间不低于冬至日照1小时或大寒日2小时。

Florescence is long , the condition suits to all can blossom all the year round almost , main florescence is solstitial spring .

花期长,条件适合几乎一年四季均可开花,主要花期冬至春季。