Photo by Vortex Farmacy[1].

Anyone who has had the good fortune to attend a HIGH TIMES Cannabis Cup[2], a similar event or a good dispensary will have noticed the wide palette of colors to be found in the various strains of weed.

If you regularly visit a grow site, you’ll see that some strains change color as they flower.

The many strains of cannabis come with different cannabinoid ratios, flavor profiles and anthocyanins[3], which are the blue, violet or red pigment prevalent in purple fruits and veggies like plums, pomegranates, blueberries and eggplants.

The most prominent variation to green cannabis is purple.   

An informative article published in Westword[4] sheds some light on the topic. For the non-scientists among us,who are intellectually curious, let’s break it down.

Color and phytochemicals[5], which are chemical compounds produced by plants to help them thrive or thwart competitors, predators or pathogens, can appear in different hues depending on pH levels. These can fall anywhere on a spectrum of blue or purple, and occasionally red.

The colors in each nug are dependent on strain genetics. Each strain’s growth process triggers genes that connect to specific color ranges, meaning that each color we see has its own phytochemical.

Westword[6] lists them for us:Anthocyanin – Blue/PurpleAnthoxanthin – White/CreamCarotenoids – Yellow/OrangeChlorophyll – GreenLycopene – Red

“When the plants feel it’s harvest time, nature invokes the change, allowing marijuana flowers to mature into color like autumn leaves until they’re ready to be plucked,” write author Chuck Haze for Westword. “This is when each phytochemical blooms, showing us the full-color spectrum of what each strain has to offer.”

Pistils, those tiny hairs that cover buds, are the female organs of a flower and are more important than you might think.

They function as pollen-catching hairs that pop out of the calyx[7]—the green outer whorl of a flower—during the plant’s vegetative stage.

Per Westword: “They are ghost-white until the plant reaches its flowering stage. At that time, their priorities switch from sprouting to pollen-catching; that pollen either births seeds or aids bud growth.”

“Once the nugs are fattened, the pistils are done vacuuming pollen and fizzle out into various colors from fire-red to tan or burnt orange.”

This is sometimes called the Fall Effect[8].

While phytochemicals and pistils are essential to each nug, they are not indicators of THC content; however phytochemicals do contain antioxidants.

In fruits and veggies, phytochemicals affect color, taste and smell, but in cannabis they only affect the color.

Some scientists believe there is a link between phytochemicals that provide antioxidants and health benefits from eating cabbage, raspberries and red onions, as well as the phytochemicals that spark color changes in cannabis.

But, as with all things cannabis, more research is required.

RELATED: A Closer Look at the Color Purple in Cannabis[9]You can keep up with all of HIGH TIMES’ marijuana news right here.[10]


  1. ^ Vortex Farmacy (
  2. ^ Cannabis Cup (
  3. ^ anthocyanins (
  4. ^ Westword (
  5. ^ phytochemicals (
  6. ^ Westword (
  7. ^ calyx (
  8. ^ Fall Effect (
  9. ^ A Closer Look at the Color Purple in Cannabis (
  10. ^ right here (

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