Why do poinsettias change colors?

Answer 1

Poinsettias require short days and long nights in order to bloom and for their bracts to turn color. They need total blackness if possible; you don't even want the light from the moon or stars to enter the room where the poinsettias are being kept.

It will take a while but the poinsettias will turn red by doing this.

(http://www.howtodothings.com/home-garden/how-to-make-a-poinsettia-turn-red)

Answer 2

The type of pigment that predominates, the latest marketing strategy and the Christmas tradition are the respectively biochemical, economic and symbolic meanings of the particular colors of poinsettias (Euphorbia pulcherrima).

Specifically, the pigments that can be tapped within poinsettias include chlorophylls, carotenoids and anthocyanins. Green is due to chrlorophylls. Ivory, orange and yellow are due to carotenoids. Blue, purple and red are due to anthocyanins.

Red is the traditional poinsettia color. But there is an interest in other colors since the end-of-the-year coincides with a number of celebrations and therefore with a number of festive color possibilities other than the Christian-linked green and red. Other colors are achieved in labs and then tried out in greenhouses, nurseries and ultimately marketplaces country- and world-wide.

The link with religious rituals explains the poinsettia's symbolic meaning and the continued popularity of the plant's natural green and red colors. In their native southwestern Mexico, they were considered by indigenous peoples to be ancient symbols of spiritual purity because of their bright, end-of-the-year blooms. The symbolism and the use were reinterpreted and applied in Christian terms by Franciscan missionaries and Spanish-speaking Catholic settlers of Mexico from the 17th century onwards. The traditional interpretation and use were continued with the plant's introduction into the United States of America in the 19th century and with its widespread cultivation and marketing through the efforts of the Ecke family of Magdeburg, Germany and California in the early 20th century.

Answer 3

The presence of carotenoid pigments is responsible for poinsettias (Euphorbia pulcherrima) turning white.

Specifically, the color of blooms and leaves is a chemical response to specific conditions of heat, light and moisture. The traditional red color of poinsettias is due to the presence of anthocyanin pigments. Carotenoid pigments also are responsible for the production of orange and yellow colors in the plant's modified leaves (bracts).

The scientific and technological changes of the 20th and 21st centuries make possible changes in the plant's internal structure and biochemistry that result in many more color possibilities than the traditional red. Nevertheless, red is still the most popular and highest selling of all poinsettia colors.