Why Is Some Weed Purple?

Purple weed strains are gorgeous, much-coveted variations of the cannabis plant. They look delicious, and many users claim that they’re stronger than the usual green stuff. Unfortunately, that one’s a myth. Purple and green buds are pretty much interchangeable. There are plenty of myths about how purple weed grows, too, so let’s get to the bottom of it: why is some weed purple?

Let’s get the myths out of the way first. People claim that you can turn your weed purple by the following methods:

• Oxygen deprivation.Plants need oxygen to grow. A lack of oxygen will stunt the plant’s growth, not change its color.
• Excess nitrogen.Plants also need nitrogen to grow, but more is not Excessive nitrogen will burn the plant, not change its color.
• Altering the light cycle.Plants need a certain amount of light during the day to stay healthy – if you mess with that too much, your plants will become unhealthy. They will not change color. 
• Changing the amount of water. In the wild, plants suck up a different amount of water every day. Cannabis is the same way. More or less water may harm the plant, but it won’t turn it purple.

A batch of weed turning purple comes down to three things: genetics, temperature, and the soil’s pH balance. Growers who want a batch of purple cannabis need to pay attention to all three, but genetics is the most important. Without a genetic predisposition to turning purple, the strain won’t be able to do it – no matter how carefully the temperature and pH are controlled.

Purple-hued cannabis gets its color from the same source as blueberries: water-soluble pigments called anthocyanins. These anthocyanins are more prevalent in some strains than others, which is why some strains are more prone to “purpling.” When a strain predisposed to purpling switches to its winter cycle of flowering, it will change colors. This is because the cold breaks down chlorophyll, allowing the anthocyanins to overpower it. To some extent, the soil’s pH level will determine the color of the anthocyanins. 

Growers can induce a “winter” cycle for a crop by gradually reducing the temperature of the plant’s environment during the dark cycle. However, this can stunt the crop’s growth if it is done too much or too quickly, and can reduce the amount of THC that will be present in the final dried bud. Fortunately, manyfamous purple strains have been bred with pigment in mind. Now, many of them turn purple more easily, without damage to the strain’s THC production. Thanks to this selective breeding, purple weed is just as dank as it looks!