grow purple weed

How to Grow Purple Marijuana – The Full Guide

For some cannabis growers, creating purple marijuana plants is their Holy Grail. The primary reason is that it is aesthetically pleasing. Showing the ability to cultivate purple weed also helps showcase your skills as a grower. However, don’t assume that the purple plants you create are somehow ‘superior’ to weed with the traditional ‘green’ color.

One popular misconception is that purple marijuana is more potent. In reality, it all depends on the strain.

Granddaddy Purple is one of the most famous cannabis strains around, and it is incredibly potent. However, like a plant’s coloring, its potency is based on genetics. Some purple weed is powerful, some offers an average THC level.

In this guide, we provide you with a concise guide to growing purple cannabis. This includes the right and wrong ways to proceed. First, let’s look into the factors that determine a marijuana strain’s color.

What Causes a Cannabis Strain to Turn a Certain Green or Purple?

You’ll notice that most cannabis plants are green. Like the majority of other plants, weed uses a pigment called chlorophyll to convert light into energy, which it uses to grow. It so happens that plants don’t have a use for the light spectrum’s green wavelength. Chlorophyll seems to have a green color because it absorbs all colors but reflects green back. This is why the majority of vegetation is green.

However, plants use an assortment of other pigments to turn sunlight into energy. These include anthocyanins which absorb all wavelengths from the sun except colors in the indigo spectrum. This is what gives plants a purple tint. Therefore, purple plants have anthocyanins as the dominant pigment instead of chlorophyll.

What Parts of the Cannabis Plant Change Color?

Here are the four main parts that offer colors apart from green:

  • Leaves: Your plant’s fan and sugar leaves can change color, but won’t have much of an effect on the color of the bud. It is perhaps the leaves that provide the most striking appearance when purple pre-harvest.
  • Pistils: These are the hairs that come out of the buds and let you know your plant is female. In general, they begin with a white hue, before turning brown, red, or orange. However, they can become purple or pink. Best of all, the color remains after you have harvested, cured, and dried your weed!
  • Calyxes: These small pods comprise your buds. Hundreds of calyxes stacked upon one another make up the cannabis flowers.
  • Trichomes: These tiny crystals cover the buds and usually begin with a glistening frosty white color. As harvest time comes and goes, the trichomes become amber. However, you can turn them purple.

3 Steps to Growing Purple Cannabis

There are ways to boost the purple coloring on your marijuana. However, without the right genetics, you have no chance of succeeding.

1 – Choose Purple Genetics

The genetics of a strain has the most significant impact on the final color. If you pick cannabis that doesn’t have a propensity to turn purple, you are wasting your time. Genetics also plays a considerable role in THC or CBD content and flavor. Here are a few good options to consider:

  • Granddaddy Purple
  • Purple Queen
  • Frisian Dew
  • Purple Trainwreck
  • Smooth Smoke

You also need to pick a strain where as many parts of the plant as possible are colorful. Ideally, the plant will have pistils and calyxes with a purple color.

The complete comparison…

A good tip is to look for intense purple buds as these provide maximum color after the drying and curing process. These deeply colored strains are sometimes called ‘black’ strains and are more vibrant when dried and cured. Once again, it is best if the color goes through the buds.

Remember that your buds will lose color after trimming, so take this into account.

2 – Adjust the Temperature

Some colorful strains only show their magnificence when the grow room temperature is a few degrees cooler at night than during the day. Ideally, you will perform this process during the flowering stage. Keep the daytime temperature between 75- and 80-degrees Fahrenheit. Move it down to the 65-70-degree range at night. Colder temperatures cause chlorophyll production to slow down and encourages the strain to produce more anthocyanins.

However, certain strains don’t react to this tactic. Some, like Panama, change color regardless of the temperature because of its genetics. Querkle, on the other hand, is more likely to show its color with warmer days and standard night temperatures.

3 – Use Powerful Lighting

Certain purple strains produce a more vivid color after exposure to intense, direct lighting on the leaves and buds. This is a method you need to experiment with to see if a specific strain reacts. Keep a close eye on your weed to ensure it doesn’t suffer from light burn. This is a risky proposition and isn’t necessary if you pick strains with the right genetics, to begin with.

Is There Anything Else That Can Help Turn Cannabis Purple?

Few other methods are tried. However, there is a suggestion that pH content matters. In the plant world, there are species that change color based on the pH level at the roots. More research is needed as it is a rarely attempted tactic.

One seed producer claims that one of its strains produces reddish or pink pistils when the soil pH is close to 7.0. You could try it for yourself, but it is difficult to know if you need more a more acidic or alkaline growing medium.

Otherwise, there is little more to it! Pick the right genetics and play around with slightly lower nighttime temperatures. You could also try the lighting tip but approach with caution. Also, it is best to grow the weed indoors as it is easier to control conditions.

What to Avoid When Growing Purple Cannabis

There are several myths and falsehoods attributed to cultivating purple marijuana. While some are silly, others are downright dangerous to your plant. One such suggestion is that you should deprive your plants of CO2 or oxygen.

Another is that adding extra nitrogen to the soil will help your plants turn a deeper shade of purple. This process could lead to a color change. Unfortunately, it relates to the sickly yellow hue associated with a nutrient burn!

Yet another unhelpful method is to reduce phosphorus intake. Messing around with nutrients will only lead to trouble.

In addition, you should only decrease the night time temperature by a maximum of 15 degrees Fahrenheit. Some growers believe that plunging it 30+ degrees will lead to purple cannabis. What’s more likely is that your plants go into shock. At best, your crop’s growth is stunted. The worst-case scenario is dead plants!

Finally, please avoid adding artificial dye! The color of the harvest is genetically encoded. Marijuana strains that are not predisposed to turning purple won’t. The only thing you’ll achieve by adding purple dye to the buds is the potential increased consumption of toxins.

Final Thoughts on Growing Purple Marijuana

Ultimately, there is no magic formula that turns weed purple. It all depends on a plant’s genetics. Don’t purchase Green Crack, Green Door Kush, or Green Dream in the hope you can turn it purple. Instead, focus on the following:

  • Purple Kush
  • Ayahuasca Purple
  • Purple Haze
  • Shaman
  • Purple #1

The purple color is all about the anthocyanin content of the strain. Without it, you can’t expect to enjoy the gorgeous purple weed you crave.

Finally, there is no reason to become obsessed with purple cannabis outside of bag appeal. There is no scientific evidence that it is any stronger or better than traditional ‘green’ marijuana. If a seller tries to claim that purple bud is better, you should ignore them and find a new dispensary!

If you are looking to grow some purple weed, then this step-by-step guide will take you through the complete process. Here's all you need to know.

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.