How does light affect the growth and development of flowers?

The intensity of light affects the opening time of flower buds and flower color. For example, Portulaca grandiflora (rose moss) opens under strong light, Mirabilis jalapa (four o'clock flower) opens in the evening, Ipomoea (morning glory) opens in the morning, and Epiphyllum oxypetalum (night-blooming cereus) opens at night.