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How to Grow Purple Cannabis

Every grower has fantasised about harvesting big, purple buds at home. But what exactly can you do to manipulate the colour of your weed?

Purple cannabis certainly does exist, but there’s a right way to turn your pot purple, and a wrong way.

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HOW TO GROW PURPLE CANNABIS

Purple weed is real eye candy. And while there are many rumours circulating the internet about how to grow purple cannabis at home, there are really only two variables that you can play with to manipulate the colour of your weed. Keep reading to find out what they are.

WHAT CAUSES CANNABIS TO TURN PURPLE?

All plants have naturally occurring pigments. The most dominant pigment in most plants (including cannabis) is chlorophyll, which, apart from helping plants photosynthesise, also gives them their green colour.

However, plants also have many other active pigments, including carotenoids and anthocyanins. In the absence of chlorophyll, plants may use pigments like anthocyanins to absorb sunlight and photosynthesise. Unlike chlorophyll, anthocyanins naturally absorb all wavelengths from the sun except those in the indigo spectrum, which is what gives plants their purple colour.

Hence, purple cannabis plants (or any purple plant for that matter) get their colour because the dominant pigment in their leaves and flowers are anthocyanins, rather than chlorophyll.

WHAT PARTS OF CANNABIS CAN TURN PURPLE?

There are four main parts of your cannabis plant that can turn purple:

• Pistils: Pistils are the fine hairs that pop out of your buds, letting you know they’re female. Pistils generally start off a creamy white colour and turn orange/red/brown as plants mature. However, it is possible for your plant’s pistils to turn pink or purple, and this colour will remain after you harvest, dry, and cure your buds.

• Calyxes: Calyxes are the small pods that make up your buds. Cannabis flowers are actually made up of hundreds of these small calyxes stacked on top of one another. As the flowers mature, the calyxes open and reveal their pistils, which are designed to catch pollen from male cannabis plants.

• Leaves: The fan and sugar leaves of your cannabis plant can also turn purple. However, they usually won’t have a large effect on the final colour of your buds, as you’ll likely trim away most of the leaves during your post-harvest work.

• Trichomes: Trichomes are the tiny crystals that cover your buds. While they usually start off clear and become opaque and then amber later on, it is possible for them to turn purple, too.

THE WRONG WAYS TO TURN YOUR POT PURPLE

Many people mistakenly believe that the best way to turn cannabis purple is to deprive their plants of oxygen. However, depriving your plants of oxygen, carbon dioxide, or any other gas will not improve your chances of harvesting purple buds. Feeding your plants more nitrogen also won’t change the colour of your plants, at least not unless you overdo it and end up burning them to a crispy shade of brown.

Some growers also use food colouring to dye their plants. And while it might work, we definitely do not recommend trying it. Finally, changing your plant’s light cycle, watering schedule, or grow medium also won’t increase its chances of turning purple, nor will yelling, screaming, or singing to your plants.

THE RIGHT WAYS TO TURN YOUR PLANTS PURPLE

Now that you know how NOT to go about growing purple weed, here are a few pointers to help you maximise your chances of harvesting some eye-catching purple buds this season:

1: START WITH THE RIGHT GENETICS

Genetics are going to have the biggest impact on the final colour of your plants. So, if you’re set on growing purple weed, shop around for purple strains, as they’ll have been specifically bred for their unique colour. Remember that your buds are going to lose some colour after trimming, so opt for strains with the most vibrant purple pigmentation you can find.

Keep reading through to the end of this article for some top recommendations on purple strains to grow at home.

2: ADJUST YOUR TEMPERATURES

While you might be eager to watch your plants turn purple, this will usually only happen once they’ve finished vegetative growth and start flowering. Once your plants have entered their flowering stage, try dropping your nighttime temperatures. Colder temperatures cause chlorophyll to break down and can encourage your plants to produce more anthocyanins. Ideally, you’ll want there to be a difference of 10–15°C between your daytime and nighttime temperatures.

OTHER WAYS TO GROW PURPLE WEED

There are some other ways to manipulate the colour of your plants. Most of these techniques, however, involve depriving your plants of certain nutrients, which, of course, we do not recommend doing. Even if you are able to achieve some purple colouration using these alternative methods, it will likely be to the detriment of quality, flavour, and potency.

GENETICS: THE #1 REASON WEED TURNS PURPLE

Remember, the two main factors affecting the colour of your cannabis plants are genetics and temperature. If you’re really set on growing purple weed, make sure to invest in the right genetics from the get-go.

At Royal Queen Seeds, our expert breeders have bred some killer purple strains. Make sure to check them out and add a splash of colour to your next harvest:

PURPLE QUEEN

Purple Queen is an almost pure indica variety bred from Hindu Kush and Purple Afghani genetics. She flowers over 9–11 weeks and produces big, purple buds with a uniquely pungent aroma that combines hints of both pine and fuel. Purple Queen also boasts a THC concentration of up to 22% and produces a nice, relaxing body stone that’s perfect for whenever you need to unwind and relax.

Perhaps you've seen brilliant purple bud. Perhaps you've even accidentally grown it. Now, you'd like to do it on purpose. Here is the ultimate guide to making your bud glow with that unique purple hue.

How to Grow Pink or Purple Cannabis Buds

Table of Contents

Would you like to grow colorful cannabis buds? You may have seen marijuana buds that are pink, purple, red, orange, or possibly even blue! But how do you grow colorful buds at home?

If you want to grow buds that are pink, red, or purple, you must choose the right genetics!

The tendency to turn colors is almost 100% determined by strain/genetics, so you can’t force any plant to produce colorful buds. However, you can purchase seeds of strains that naturally turn vibrant colors, and there are tricks to maximize their genetics and bring out the colors of your buds.

You cannot produce buds this purple without a strain that has been bred to makes purple buds. There are tricks to maximize the natural color of your genetics, but you have to start with good genes!

4 Different “Parts” of Cannabis Can Become Colorful

When people are talking about “colorful” buds, most people imagine brightly colored buds in their hands. But there are actually different parts of cannabis plants that can display non-green colors, and sometimes people will lump all them all together. Each one is a little different from each other, and some have a significant effect on the final looks of your bud, while others don’t make much difference.

Many different parts of a cannabis plant can turn purple, including the whole plant!

The parts of the plant that can become colorful are…

  • Pistils (Hairs) – some of the color remains after drying/curing
  • Calyxes (Buds Themselves) – very strong effect on final color
  • Leaves – relatively small effect on final bud color since many are removed by trimming
  • Trichomes – small effect on final color

Buds are made up of different parts and are usually more than one color

Colorful Pistils / Hairs

Most growers want the buds themselves to appear colorful, so the color stays even after the buds are dried and cured.

There are two parts of the buds that can turn color. One part is the pistils/hairs that stick out. There are several strains where the pistils turn pink or purple.

Sometimes just the pistils/hairs turn pink or purple, while the leaves and buds may still be green.

When buds are dried, they retain some of their pistil color, but you will still be able to see the color coming through underneath.

Colorful Calyxes (Buds Themselves)

Calyxes are what make the buds themselves. Cannabis “buds” are actually made of hundreds of calyxes stacked on top of each other, and some or all of them may become colors other than green.

This fantastic picture shows how the overall appearance of buds changes with the ratio of colorful vs. green calyxes.

Nearly all Smooth Smoke buds (by Tropical Seeds) produce at least a few pink calyxes here and there, and some plants in the right conditions can produce buds where almost every calyx is a deep purple.

Calyxes are what give the most color to your buds. Even a few purple calyxes can give the buds an overall purple tint, and when you break open the buds there will be some pieces that are completely purple.

This nug contains several purple calyxes.

After being ground up, you can see the purple pieces distributed throughout. The higher the percentage of purple calyxes, the more vibrant your final bud color will be.

Colorful Leaves – Sometimes It’s Not the Buds That Turn Color!

With some strains, the leaves may turn purple while the buds stay mostly green. This can make for absolutely gorgeous plants, but since leaves mostly get trimmed off after harvest, usually, a lot of the purple will no longer be visible on the buds after the trimming process.

For some strains, the leaves may turn purple while the buds stay green. This often happens after the plant gets exposed to chilly night temperatures (but not always). The leaves exposed to direct light are most likely to turn purple, while leaves in the shade often stay green.

Although the leaves have turned purple, the buds themselves are mostly green.

Only the tops of buds exposed to direct light have any purple left after trimming off all the leaves. Trimming removed almost all of the purple coloring.

Colorful Trichomes

In general, cannabis trichomes go from clear (not ready) to white (highest THC) to amber/yellow (more of a mellow effect) before they eventually wither and die. These color changes are often used to determine the best time to harvest cannabis.

However, sometimes, trichomes can turn purple or pink, making it difficult to know when to harvest. In that case, you want to also look at the pistils to determine the best harvest time!

Purple or pink trichomes can make it tough to know when to harvest, but they’re exotic and beautiful! The color of trichomes may leave a slight tint on the buds after they’ve been dried and cured, but the bud color underneath will be the dominant color.

Now on to making purple buds at home!

How to Maximize Color and Genetics

Before you do anything else, you need to begin with the right genetics. If the genes of your plant don’t make colorful buds, there’s nothing you can do! So, you must start with a colorful strain to get the best results with maximizing color.

  • Choose Colorful Strain (Most important!)
  • Choose Strain that Produces Very Dark Colors (if you want buds to maintain color after being harvested and dried)
  • Temperature – Warm days & cool nights
  • Bright Light – Strong light levels can help bring out color
  • PH at the Roots – Some strains may express colors at higher or lower pH ranges

Choose Strains with Brightly Colored Buds and Pistils If Possible – This maximizes the overall colorful appearance of your buds.

For the most significant final effect on your dried and cured buds, you want to choose a strain where as many parts of the plant as possible are colorful. So ideally, you want buds where the pistils and calyxes (which make up most of the final color) are both vividly colored. If the leaves and trichomes are also colorful, that will improve the effect even further.

In this case, the buds are purple, but the pistils are orange.

To maximize the final color, you want to choose a strain with brightly colored buds and pistils. For example, this bud has purple calyxes, mostly purple pistils and even some purple leaves. This combination makes the entire bud appear bright purple.

Choose Deep Purple Buds for Maximum Color After Drying/Curing – Deeply colored buds (sometimes called “black” strains) tend to be the most vibrant after drying/curing.

To produce the most colorful buds, you need to make sure the color goes all the way through the buds, and ideally, also through all the surrounding leaves. This level of color-penetration is most likely to happen with intensely dark colored buds. Buds that are paler in color tend to lose a lot of their vibrancy in the post-harvest processing.

These buds were mostly pink at harvest, but the color doesn’t go all the way through the buds.

There was still a lot of green on the parts of the buds that didn’t get direct light.

After they’re trimmed and dried, the pink color has become more subtle.

You will “keep” the most color after drying/curing by choosing strains that are dark purple through and through, from buds to pistils to leaves if at all possible. Deeply colored buds keep more of their color after drying and curing than pale purple or pink buds.

These buds were deep purple at harvest…

When buds are darkly colored, they tend to keep more color after being dried and trimmed.

Note: Your buds will naturally lose some of their overall vibrancy and color during the drying/curing process (but not any of their potency!). That’s why you will likely never run into neon purple buds that have already been dried and cured for 2+ weeks. Even green buds go from being bright green to a more muted green color by the time they’ve cured for a few weeks. When you see very brightly colored buds, it almost always means the buds are still relatively fresh.

Although color is determined primarily by genetics, there are a few things you can do to help your plant express its natural colors…

Temperature – Some Strains Express Colors When the Night Temperature is a Few Degrees Cooler than the Day

If you’re growing a strain that turns color, some strains will only show their colors when night temperatures are at least a few degrees cooler than during the day in the flowering stage, especially towards the end. However, some plants don’t react to cool night temperatures, and many strains (like Panama) nearly always turn color no matter what the temperature.

Certain strains like Querkle turn color more easily when the temperature is warm during the day as opposed to cool at night. So, it’s always a good idea to aim for nice warm days, and cool, comfortable nights, because that contrast seems to help bring out colors for many strains.

How to Maximize Color with Temperature

  • Warm Days (75-80°F / 24-27°C)
  • Cool Comfortable Nights (65-70°F / 18-21°C)

Note: Some strains turn color no matter what the temperature. You can sometimes contact the breeder and ask if they have advice on how to bring out colors for a particular strain. I’ve found that most breeders will get back to you quickly if you go to their website and ask questions!

Temperature makes a difference! Some strains need contrast between day/night temperatures for their buds to turn colors. For example, the buds of this Auto Frisian Dew turned bright purple after it started getting below 70°F (21°C) temperatures at night.

Strong, Direct Light may help bring out colors

In some cases, a plant may produce purple tones in response to intense, direct light (on buds and leaves). Although we’re not sure exactly why it’s possible this may act as a sort of sunscreen for the plant! The importance of light levels varies on a strain by strain basis.

The pH at the Roots may affect cannabis bud color expression

Outside the cannabis world, there are a few species of plants with flowers that are known to turn different colors based on the pH at the roots.

For example, the flowers of specific types of hydrangeas can turn blue in very acidic soil but may turn pink if exposed to neutral or only slightly acidic soil (though this type of variation is rare in the plant world).

Yet there have been occasional reports of cannabis strains that produce different bud colors based on the pH at the roots, though unfortunately, more testing is needed!

If growing multiple plants of the same strain, you might consider giving plants different pH ranges to see what effect it has on the final bud color!

Pictures and Examples of Colorful Strains

Here are some pictures of cannabis strains that sometimes grow colorful purple and pink buds.

Photoperiod (Regular) Strains

Frisian Dew

The next two pics are of the strain Frisian Dew, a popular strain by Dutch Passion, who specifically designed the strain for growing outdoors. It is exceptionally hardy, high yielding, and is also mold and pest resistant. About 50% of the time, Frisian Dew buds will turn bright purple instead of green!

The plant in the middle with the dark purple buds is Frisian Dew.

Purple Trainwreck

Purple Trainwreck buds are usually purple-tinted, with purple leaves or pistils.

This Purple Trainwreck plant is growing purple pistils.

For this Purple Trainwreck cola, it’s mostly just the leaves turning purple. In either case, the effects are the same!

This Purple Trainwreck bud turned particularly purple.

Panama

The following plants with pink pistils are from the strain Panama by Ace Seeds

This is what Panama buds may look like when they’re first growing in.

beautiful pink pistil pic by trippergreenfeet

As the Panama buds develop, the pistils and even the buds themselves may intensify their pink color

Smooth Smoke

Smooth Smoke buds (by Tropical Seeds) can become quite colorful, with colors from hints of pink to deep purple!

Auto-Flowering Strains

Auto Frisian Dew

Auto Frisian Dew by Dutch Passion (this is an auto-flowering version of the original famous marijuana strain) – Unlike the regular Frisian Dew which gets about 50% purple bud plants, the breeder claims only 10% of the plants from this strain produce purple buds. Still, some growers are getting far better odds than that. When purple does appear, the color is incredibly vibrant and spills out onto the nearby leaves!

This Auto Frisian Dew plant got a little stunted at first, but still ended up producing beautiful purple buds!

Auto-Flowering Bloody Skunk

Auto-Flowering Dark Devil

Dark Devil Auto is another fabulous auto-flowering strain by Sweet Seeds that turns a gorgeous purple or even a deep red.

This Dark Devil Auto bud turned completely purple from top to bottom.

Purple Kush Auto

Brilliant color on Purple Kush Auto plants! The buds turn almost black after being dried!

pics by kingkola1

Colorful “Duck” Strains (Stealth Leaves)

“Duck” strains are characterized by their oddly shaped leaves. The idea is that the plants look less like cannabis with 3-finger leaves. The bright colored buds also help make them look less like cannabis.

Frisian Duck

One of the most popular variations of the Ducksfoot (Ducksfeet?) strains is called Frisian Duck by Dutch Passion. This strain thrives outdoors and grows with the traditional stealthy leaves. This strain also often makes bright, beautiful purple buds (with cold enough temperatures) that have a fresh scent that is sometimes even a little fruity.

Frisian Duck plants react well to growing in a living soil that’s been composted and amended with slow-release organic ingredients.

This is a Frisian Duck plant in the vegetative stage.

This Frisian Duck plant was grown outdoors in a greenhouse. More than half of Frisian Duck plants grow bright purple buds!

Frisian Duck is based on the famous Frisian Dew strain which also produces purple buds and has been bred for generations specifically for growing outdoors. The Frisian genes thrive under sunlight, and buds are resistant to bugs and mold!

This Frisian Duck plant is just about ready to harvest!

However, even with stealthy strains, be aware that they still smell like cannabis in the budding stage!

Why Do Cannabis Leaves and Buds Turn Purple?

Sometimes you’ll see purple leaves because of a nutrient deficiency, but oftentimes purple leaves are actually caused by natural plant processes!

There are many species of plants that make purple leaves. The leaves appear purple due to high levels of a purple pigment called anthocyanin. Anthocyanin may act as a sunscreen for plant leaves because it protects against damage caused by UV-B rays. Anthocyanin is also known to help protect against cold or heat stress on the cellular level.

It’s not just cannabis plants that grow purple leaves. Here’s an example of a False Shamrock plant, which has glorious purple leaves from top to bottom!

With some cannabis strains, the leaves may turn purple while the buds stay green. Just like with buds, the leaves are more likely to turn color when the plants are getting cool night temperatures in the late flowering stage.

The leaves most likely to be affected are the top leaves and other leaves getting direct light. With this purpling, the leaves in the shade of the plant usually stay green.

For some strains, the leaves may turn purple while the buds stay green.

The leaves of this plant turned purple overnight after that plant was exposed to chilly night temperatures.

The leaves exposed to direct light are most likely to turn purple, while leaves in the shade often stay green

In this case, all the leaves that are exposed to the light have turned purple, including the sugar leaves. However, once the leaves are trimmed off, the buds will be mostly green.

Buds may still be purple-tinted from leaves that weren’t completely trimmed off.

If there’s a lot of purple leaves, there may be a lot of color left even after trimming.

Case Study – Super Purple Haze plant

The top leaves of this Super Purple Haze plant have turned a vibrant purple

Here are the buds from that Super Purple Haze plant drying – you can see that the parts of the buds that were exposed to the light have strong hints of purple

A closer look at those buds so you can better see how much bud is purple and how much is green after being trimmed and dried (click for a closeup!)

This cannabis plant has grown vibrant red and purple leaves.

This outdoor cannabis plant has turned purple everywhere it received direct sunlight. Splendid!

Cannabis sometimes has neat mutations, like this two-tone plant where only half the leaves turned purple!

These Swiss Cheese plants by Nirvana exploded with red, pink and purple leaves when it got cool at night right near harvest time, but the buds themselves did not change color. Unfortunately, when just the leaves turn color, the buds themselves will often look mostly green once they’re trimmed. But this beautiful picture lives forever!

Bright purple stems may be a sign of a phosphorus deficiency, but this “symptom” is sometimes actually caused by genetics, just like purple leaves, pistils or buds!

Blue Dream (rare deep purple phenotype)

Blue Dream buds usually don’t turn this deep purple, so if you want to see buds like this you’re better off with a strain that’s bred to always grow dark purple buds. However, the pictures were so beautiful I just had to share!

How can you grow colorful buds that turn purple or pink? Learn which strains to get, as well as what you can do to maximize color during your grow.