Sorry, I can not type chinese now . F( Z# T9 j' }" E* A' ` # t1 [( o$ E' i0 V- M+ vBut, I put the poinsettia in a seperate room which should have more than 10hrs black time. Maybe it need more sun light?
at least 10hrs darkness, you can treat it 10~14hrs or longer ,it does not a matter, just a couple of hrs of sun light. and hopefully it can change corlor 3 weeks later till x-mas day.