Article by Madison Margolin, Motherboard
Before cannabinoid testing and genetic profiling of the cannabis plant, consumers would judge a batch of weed based on its smell, taste, and color. In fact, a whopping 93 percent of buyers make a purchasing choice contingent on the color and look of the bud.
The color of cannabis is not constant, but rather changes with the plant’s maturity. According to the pH or acidity levels of the plant, its anthocyanins—water-soluble pigments—may appear blue, red, or purple. Anthocyanins appear in other plants as well, such as blueberries and eggplants.
The color of a cannabis plant is also influenced by temperature: In cooler environments, the plant produces less chlorophyll, green pigments critical to photosynthesis, which allows a plant to absorb energy from light. The colors of cannabis can be manipulated by managing the acidity levels and temperatures in which the plant is bred. Altering these various levels can bring out different colors and qualities, while inhibiting others.
One of the most popular alternatives to green is purple—think Granddaddy Purple. Purple pigments occur fairly easily in the cannabis plant, as it begins to lose chlorophyll as it matures into old age. However, before the bud gets too old, purple pigmentation can also be engineered in neutral pH environments.
Reddish strains are harder to come by, but can be bred by manipulating nutrients and depriving the plant of phosphorus. The darker, even black appearing strains, are caused by an excess of pigmentation in the cannabis’ leaves. These strains are also known for more intense visuals and psychedelic highs. They usually thrive in somewhat cooler temperatures, since in warmer environments the dark, deep reds and purples may become lighter.