HORTICULTURE

Detailed explanation-1: -Poinsettias (Euphorbia pulcherrima) are popular winter houseplants because they flower in mid-winter, and because their beauty is the result of bracts (persistent colored leaves) instead of flowers, their attractiveness is long-lasting.

Detailed explanation-2: -In order for a poinsettia to change color, it needs twelve hours of darkness for at least five consecutive days. After the color change process has taken place, poinsettias need at least six hours of indirect sunlight per day to maintain their brightest color.