Cannabis leaves and flowers can also vary in hue, offering a full palette of marijuana colors to please the eye. Several different factors can influence marijuana colors, including temperature, nutrient levels, the acidity or alkalinity of the soil or other growing medium, and the quality of the light.
Green is the predominant color of most flowering plants including cannabis because of the presence of chlorophyll, the pigment that absorbs sunlight (except the green wavelengths) to power the process of photosynthesis.
Cannabis flowers that are purplish, red, blue or pink are generally high in a group of chemicals known as anthocyanins. They belong to the class of substances known as flavonoids and have antioxidant properties.
Carotenoids produce the yellow, orange, and red hues that are found in many plants including carrots, squash, sweet potatoes, pumpkins, tomatoes and, yes, marijuana. Carotenoids are important for eye health and provide protection against blue light and macular degeneration.
Buds that have been grown and harvested to their maximum potential can be so covered with trichomes that they appear white or frosty. Trichomes are packed with cannabinoids and terpenes so these flowers can be quite potent.
See the original article at High Times