Why Does Weed Turn Purple? Truths and Myths about Purple Cannabis
Thursday April 5, 2018
I n these modern times of cannabis consumption bad information still runs rampant, and few things in the world of weed have as large a mythic standing as purple bud. This seemingly simple topic can actually be a bit convoluted, starting with, what is purple bud? The short answer is cannabis flowers that exhibit a darker, purple-tinged hue. However, it is not always the shade most people think of as “purple.”
Purple cannabis can be a tricky concept. Just stop for a moment and contemplate the timeless line, “roses are red, violets are blue.” A modern sensibility would correct that the color of violets is none other than violet. Similarly, purple weed is not always “purple.” It can have a wide range of presentation, from dark green to even black.
Why is Some Cannabis Purple?
Consider that what we call a blueberry is also usually quite purple. This is because the very thing that makes blueberries “blue” is the same as what makes purple nugs “purple,” anthocyanins. Anthocyanins are water-soluble pigments present in many plants. Despite the “cyan” in “Anthocyanins” referring to their blue nature, these molecules occur in a range of colors from red to purple to dark blue, or black, depending on pH level.
Anthocyanins are part of a larger class of substances known as flavonoids, which aside from how the name sounds, have very little to do with flavor (and are astringent to the taste). In fact, the “flav” in flavonoids comes the Greek word for yellow, flavus.
This can be a bit linguistically confusing; a blue-named class of molecules that presents as red or purple is a subset of a class of yellow-named molecules. It begins to make sense when we consider that a complex interaction of anthocyanins and other flavonoids is what causes leaves to change their color among such a brilliant spectrum in the fall.
When cannabis presents as purple, we are seeing a similar phenomenon as fall leaves, allowing purple bud to have a wide spectrum as well. Like other plants for cannabis, colors, and changes in color, have purpose. The stressed plant is changing pigment in order to achieve a goal before wilting in the cold, such as conserving energy or increasing chances for pollination.
For cannabis strains, the ability to present darker pigments, and to what degree, is wholly dependent on the plant’s genetics.
Without a predisposition to purpling, a given strain cannot be induced to turn purple. Certain strains will have more naturally occurring anthocyanins than others, and when switching to the “winter” cycle of flowering, will start to express those purple pigments innately according to their genetic predisposition interacting with the unique chemical and environmental factors in which the plant is grown.
Is Purple Marijuana Better?
Visual appeal aside, is there reason to believe that these royal-toned flowers are better than the green hues more common to the plant? The science leans towards no.
According to the European Food Safety Authority, there is no substantive evidence anthocyanins have any effect on human biology or diseases – though they contain a higher concentration of anti-oxidants, which would theoretically only be beneficial if one were eating buds. There is some minor proven correlation to anthocyanins as an anti-inflammatory, but again, would probably be more active if ingested. Seeking a strain with higher CBD content would be a better source for anti-inflammatory effects than purple hue.
In general, purple bud has a tendency for lower THC content than its greener counterparts. That’s not to say high-THC purple is not possible, we’re sure we’ve all seen or smoked an exception to the rule. That is because most purple bud that we see today is not a result of stressing the plant, but genetics.
To better understand this connection, I spoke with veteran grower and concentrate connoisseur Matt Gosling about the popularity of purple cannabis. While purple bud can be fantastic, he explained, it’s usually due to good breeding and genetics, and not much else.
“Purples are memorable. If you have a good high with purple bud, it’s going to stand out. Then if you’re a grower and you have the ability to then reinforce those genetics you’re going to, and it propagates itself from there.”
Anything beyond breeding could detriment the plant. “Any energy the plant spends pushing out that purple pigment is going to be drawn from somewhere else and is going to hurt overall. It’s just not worth risking the quality for a chance a slightly better bag appeal.”
Myths about Purple Weed
Some people believe that there are growers out there who bring out purple hues by manipulating the plant, however, the prevalence of such practices seems to largely be a myth. I rattled off a list of alleged techniques for inducing purple bud to Matt, such as affecting nutrient levels or flash freezing, and he quickly declared them bunk.
That’s not to say attempts at purpling don’t occur at all, “I’ve seen some people use ice water to do their flush,” he told me, “some other tweaking with light timing, but I don’t recommend any of it.”
In speaking with growers, budtenders, flower reviewers and other cannabis journalists, the consensus among the industry is to treat each harvest as unique–smoke what appeals to you. If the effects of purple strain are appealing, go for it.
Furthermore, no one is wrong to feel that the visual appeal of a flower can enhance the smoking experience. However, ultimately, the mere presence of the pigment is unrelated to the resulting effects. If the flower is good, by all means smoke it, in any spectrum of the rainbow.
What are your thoughts on purple weed? Do you find it to be better than green cannabis?
Matt Mongelia holds an MFA in writing from The School of the Art Institute of Chicago. He has worked in the cannabis industry in various roles for 4 years, from dispensaries, production and retail to events, content and marketing. He is a writer for the comic Dark Beach, and has previously covered music and cultural content for SOL REPUBLIC.
Everyone cannabis enthusiast has a place in their heart for purple weed. Learn about why cannabis turns purple and some of the truths and myths behind it.
Purple Weed: Everything You Need To Know
Purple weed seems to be the holy grail that everyone is searching for these days. And they’re doing all kinds of crazy things to get it. But is there really any extra benefit to the purple hue, or is it all just bunk? And is it even possible to produce the coveted purple color by giving the plant something extra, taking something away, or tweaking the conditions in which the weed is grown?
We’ll answer those questions, and more, in the following article.
Myths About Purple Weed
Myths about purple weed abound. Most of those myths revolve around how the famous purple hue is achieved when growing marijuana. The most common myths include:
- Oxygen deprivation
- Carbon dioxide deprivation
- Nitrogen overload
- Altering the light cycle
- Changing the growing medium
- Varying the amount of water
Let’s look at each one in turn.
Sure you might turn blue if you held your breath too long, but that same concept doesn’t apply to marijuana plants. The myth that depriving your marijuana of oxygen turns it purple is patently false. Marijuana, like all living things, needs oxygen to grow. Restricting that oxygen in some way will only stunt the plant’s growth, not make it change color.
Carbon Dioxide Deprivation
Like oxygen, carbon dioxide is necessary for the healthy growth of most plants. A marijuana plant that is deprived of carbon dioxide won’t develop correctly. Carbon dioxide deprivation of marijuana is only a recipe for unhealthy weed, not for turning it purple marijuana plant that is deprived of carbon dioxide won’t develop correctly. Carbon dioxide deprivation of marijuana is only a recipe for unhealthy weed, not for turning it purple.
And really that’s just common sense. Depriving a plant (or any living thing) of the essential ingredients it needs to grow will only make it unhealthy.
Though it may sound counterintuitive, more is not always better. Plants need nitrogen to grow, but too much nitrogen can burn the plant and make it sick. Far from turning the plant purple, too much nitrogen will turn a marijuana plant brown. Definitely not what you’re looking for.
Altering The Light Cycle
This one doesn’t work to turn your marijuana purple either. Plants need a certain amount of light each day to stay healthy. If you mess with that process, you’re just going to get unhealthy plants, not purple ones.
Changing The Growing Medium
Nope, not going to make your marijuana purple. Plants use the nutrients in the soil to grow but altering the composition or quantity of those nutrients isn’t going to result in purple weed.
Varying The Amount Of Water
Again, no. Plants are accustomed to varying amounts of water. They can get what they need from the soil and from the air around them if none is provided directly. Some plants can go days and even weeks without direct watering. Marijuana is no different. Grown in the wild, marijuana contends with varying amounts of water on a daily basis and doesn’t turn purple. No, varying the amount of water isn’t going to somehow miraculously result in purple buds.
As you can probably surmise from the sections above, too much or too little of an essential ingredient isn’t going to result in the elusive purple buds. It’s only going to make your marijuana unhappy and unhealthy.
So how do you go about producing purple weed? Excellent question. But before we answer that, it’s important to understand the science behind what makes weed turn purple.
The Science Of Purple Weed
Flavonoids are a class of plant pigments. The pigments work in combination with other chemicals to give plants their distinctive, and varied color. Common flavonoids include quercetin, carotenoid, and kaempferol. Flavonoids get their name from the Latin “flavus” (yellow) because they generally appear yellow in appearance. Contrary to how the word looks, flavonoids have nothing to do with flavor.
The flavonoid that most concerns this discussion of purple weed is anthocyanin.
Anthocyanin gives plants a red, purple, or blue hue depending on the pH. If the pH is more acidic, the plant displays red. If the pH is more alkaline (toward the base end of the scale), the plant displays blue. If the pH is more neutral (in the middle between acid and base), the plant displays purple.
During the majority of the growing season, anthocyanin is overpowered by the stronger, greener chlorophyll. That’s why most plants are green in the spring and summer: the chlorophyll is more prevalent. And this isn’t just happenstance. The green color actually serves a purpose—it captures more solar energy than other colors.
In the fall then, when chlorophyll breaks down, the anthocyanin (and other flavonoids) are no longer overpowered by the green. This results in the beautiful yellows, reds, oranges, and even purples that signal the approach of winter.
Like the green, the colors are not just for show; they do serve a purpose. In this case, the bright colors that appear during the fall months attract more insects which, in turn, aid in the pollination process. It’s basically the plant making itself look more attractive so it can reproduce.
And whether a plant’s leaves turn red, or yellow, or orange, or purple is largely determined by its genetics. A plant’s genetics determines how much of one flavonoid or the other is present. So trying to force a marijuana plant to turn purple won’t work unless the traits are already there.
Understanding where a plant’s purple color comes from, and when it is more likely to come about, goes a long way toward helping us achieve the purple weed that so many desire. But before we talk about how to grow purple weed, let’s examine some of the possible benefits it has to offer.
Benefits Of Purple Weed
Most of the hype surrounding purple weed is strictly novelty. In reality, purple weed isn’t much different than green weed or multi-colored weed (e.g., Fruity Pebbles). Any extra benefits cannabis consumers claim to get from purple weed is more likely due to altered perceptions (no pun intended) or the strain itself. It doesn’t have to do with the color.
That said, anthocyanin has been shown to be an excellent antioxidant that occurs in foods like grapes, blueberries, and raspberries. High levels of these antioxidants can produce anti-inflammatory effects in the body. For this reason, foods, and perhaps purple weed, may be used with good results by sufferers of fibromyalgia, arthritis, and other inflammatory diseases. The science hasn’t been conducted on purple weed to fully support this hypothesis, but, based on the anthocyanin in purple-colored foods, it’s a strong possibility that there are some health benefits involved.
How To Grow Purple Weed
Two important factors determine whether weed can, and will, turn purple during its growing cycle: genetics and temperature. Here’s how they work.
1. Get The Right Seeds
Remember from our discussion about flavonoids and anthocyanin that it’s the presence of the latter that determines if purple is even possible. If a strain’s genetics contain carotenoid instead of anthocyanin, the color will be more on the yellow side. Nothing you can do will change that. It’s like planting a tomato plant and then trying to make it produce kiwi. It’s just not going to work.
So the first step in growing purple weed is to plant seeds that already have a predisposition toward purple (i.e., contain anthocyanin). Check out our popular strains below but Purple Haze and Sour Grape are excellent candidates to produce the coveted purple color.
2. Mimic Fall Temperatures
Plants change colors in the fall when temperatures begin to drop from their summer highs. So your best bet for producing purple weed is to mimic these fall temperatures and give the anthocyanin time to work its magic.
During the flowering stage, reduce the temperature below 50 degrees Fahrenheit during the nighttime cycle to help break down the chlorophyll and make the anthocyanin more active. Done consistently, these lower temperatures can produce a purple coloring a few weeks before harvest.
Popular Purple Weed Strains
As it’s name implies, this is the granddaddy of purple weed.
I can’t help but think of the beloved cartoon character of the same name. The animators had to be on some form of weed, dontcha think?
Hendrix had it right!
With parents like Sour Diesel and Granddaddy Purple, it just has to be good.
The high-flying effects of Diesel mixed with the healthy antioxidants of purple—what could be better?
A hybrid that, yes, actually smells like mild cheese.
In no way related to the president, this indica strain is a go-to for first-time users.
The Future Of Purple Weed
If you’re a cannabis consumer like us, you’re probably of the mind that even bad weed is better than none. And though you may have your own preferences when it come to flavor or effects, should it be found that the antioxidants in purple cannabis offer an extra benefit, the purple strains will likely become the gold standard. Smoking pot and getting healthy at the same time? Who could argue with that!
Purple weed seems to be the holy grail that everyone is searching for these days. But is there really any extra benefit to the purple hue? Let's find out.