Purple Weed: Everything You Need to Know

Purple weed is a type of cannabis that has captured the attention of many enthusiasts and curious users of this wonderful plant thanks to its unusual appearance, striking beauty, and acclaimed reputation. The chemical compounds responsible for this coloration are anthocyanins, pigments found in many plants and fruits.

Some strains of this so-called purple weed only develop purple or red buds when exposed to environmental changes (such as pH, temperature, or light), especially cold temperatures below 15 °C (59 ºF). Other strains, however, are genetically predisposed to produce high levels of anthocyanins and will always display red, purple, or bluish buds during flowering, regardless of environmental conditions.

It’s important to know that certain pH changes directly affect the color of the plants. An acidic pH causes anthocyanins to take on reddish tones, while a more neutral or alkaline pH can shift the hues toward more purple or bluish shades.

Temperature is also a key factor that can trigger these color changes in the cannabis plant. It’s well known that with lower temperatures, buds and leaves tend to take on red or purple tones. It is believed that this is how the plants try to protect themselves from light at low temperatures.

5 Purple Weed Strains from Sweet Seeds®

At Sweet Seeds®, we offer a wide range of purple weed strains, all of them of the highest quality and very appealing, all part of our renowned and celebrated The Red Family.

All of these strains show their red color expression without the need for environmental triggers or changes, as they are genetically predisposed to produce anthocyanins and develop purple, red, bluish, or even nearly black buds at the final stages of flowering.

Today we’re focusing on five purple weed strains from this family that are incredibly beautiful and attractive, both during the growing process and after harvest. These include the following:

• Red Gorilla Girl XL Auto® (SWS89)
• Red Strawberry Banana Auto® (SWS90)
• Tropicanna Poison F1 Fast Version® (SWS85)
• Diablo Rojo XL Auto® (SWS110)
• Red Hot Cookies® (SWS83)

At Sweet Seeds®, we are fully committed to high-quality genetics, whether photoperiod-dependent strains, including the well-known F1 Fast Version®, or autoflowering strains, so it’s no surprise that even the most demanding growers end up falling in love with one of these red-flowered weed strains.

Of course, everyone has personal preferences and individual tastes. Our goal is to cover as much of the cannabis gene pool as possible, without ever compromising on quality, yield, or aroma.

Our purple weed strains guarantee great potency, intense aromas, solid yields, and beautifully exotic-colored flowers. And with all of that, who wouldn’t fall in love with these cannabis genetics?

So, let’s take a closer look at the following five purple weed seed strains from the Sweet Seeds® genetic collection.

Red Hot Cookies®: Hints of Tangerine and Mango

This photoperiod-dependent strain brings together the best of purple weed genetics and the power of American strains with high THC levels, which is why we include it in our Super Strong strains category. With flavors reminiscent of fruits like mango, tangerine, and berries, it delivers a very uplifting, creative, and cheerful effect.

Its parent strains are an elite clone of Tropicanna Cookies (Girl Scout Cookies x Tangie) and a selected clone of another potent American variety with an excellent tangerine aroma: Tangie.

Once this plant enters the flowering stage, around 60% of the individuals end up developing reddish buds. Combined with its heavy trichome production, this creates a dazzling visual display. You’ll enjoy extremely beautiful plants with rich, fruity aromas.

Here’s the technical sheet of Red Hot Cookies®:

• Indica: 40%
• Sativa: 60%
• THC: 17-25%
• CBD: 0.1%
• Indoor Yield: 500-600 g/m²
• Outdoor Yield: 400-600 g/plant
• Indoor Blooming: 8 weeks
• Purple Flower: approximately 60% of the specimens

Tropicanna Poison F1 Fast Version®: an Exotic Genetic

Here we have another one of the best purple weed strains from our genetic collection. A stunning plant that will brighten up any garden with its vibrant, deep red buds and very sweet, intense aromas, featuring subtle Skunk notes, hints of wood, and a fruity touch reminiscent of mango.

This strain is a joy to grow thanks to its vigorous growth and large, dense flowers. Its flowering phase stands out for being abundant and fast, allowing it to be harvested just 6 to 7 weeks after the flowering stage begins.

It’s an ideal strain for outdoor growing in cold climates or areas where humidity is a concern, as its fast flowering lets growers harvest before mold threatens the buds of longer-flowering plants.

Here’s the technical sheet of Tropicanna Poison F1 Fast Version®:

• Indica: 60%
• Sativa: 40%
• THC: 16-24%
• CBD: 0.1%
• Indoor Yield: 450-600 g/m²
• Outdoor Yield: 400-650 g/plant
• Indoor Blooming: 6-7 weeks
• Purple Flower: approximately 80% of the specimens
• Effects: Psychoactive, Uplifting, Relaxing

Diablo Rojo XL Auto®: Sweet and Fruity Aroma 

Next up is this autoflowering purple weed strain, part of the Sweet Seeds® catalog since early 2024, which has already received plenty of praise on social media thanks to how easy it is to grow.

It stands out for producing large, dense buds and developing rapidly, completing its life cycle in just 8 weeks from germination.

The aromas of Diablo Rojo XL Auto® are intensely fruity and sweet, with citrusy and incense-like notes, hints of berries, and a background reminiscent of cola soft drinks. A flavor experience you won’t forget.

During flowering, it impresses with its massive red and deep purple buds, coated in a thick layer of trichomes. We recommend extra care during drying and curing. It is very important to ensure proper ventilation in the drying area and break up overly thick buds to prevent mold, which may form inside the densest flowers due to their weight and density.

Here’s the technical sheet of Diablo Rojo XL Auto®:

• Indica: 56,9%
• Sativa: 40%
• Ruderalis: 3.1%
• THC: 16-23%
• CBD: 0.1%
• Indoor Yield: 400-500 g/m²
• Outdoor Yield: 50-150 g/plant
• Indoor/Outdoor Harvest: 8 weeks from germination
• Height: 50-120 cm
• Purple Flower: approximately 80% of the specimens
• Effects: Stimulating, Happiness, Relaxing, Creativity

Red Gorilla Girl XL Auto®: The Gorilla Dresses in Red

Many of you are already familiar with the legendary Gorilla Girl® (SWS74) from Sweet Seeds®. This strain has gained great popularity in both its photoperiod-dependent and autoflowering versions, ranking among the most powerful cannabis strains in the world.

With its launch, we introduced the “Super Strong” label to highlight its exceptional potency. Following its success, our breeders developed a new version of this marvel: one that displays striking reddish or purple hues while enhancing its aromatic profile. The result is even sweeter and more citrusy, with spicy notes and the fresh cypress undertone, quite typical of this genetic line.

Red Gorilla Girl XL Auto® is the outcome of crossing Gorilla Girl XL Auto® (SWS82) [Gorilla Girl® x Sweet Gelato Auto® (SWS76)] with the red-flowered autoflowering strain Bloody Skunk Auto® (SWS44).

Under optimal growing conditions, this strain can reach up to 120 cm in height in just 8–9 weeks from germination. Yields can surpass 500 g/m², and it’s possible to harvest over 100 g per plant. With some training to shape its branches, you can push yields to extreme levels, while being able to harvest top-quality buds.

Here are the relevant percentages for Red Gorilla Girl XL Auto®, showing how balanced it is: 

• Indica 52.3%
• Sativa 45.2%
• Ruderalis 2.5%
• In terms of cannabinoids, this strain features around 15-21% of THC and approximately 0.5% of CBD

What Can We Expect When Growing Red Gorilla Girl XL Auto®?

In the grow room or garden, Red Gorilla Girl XL Auto® performs exceptionally well. This purple cannabis strain is a pleasure to watch as it grows and flowers. While most growers opt for organic nutrients and soil-based substrates, it’s worth noting that yields can be pushed even further when using coco or hydroponic systems.

• Growth: This is a fast-growing plant that can easily reach 80 cm in height by the time flowering begins. It typically doesn’t develop many side branches, but you can always apply a bit of LST (Low Stress Training) to the main stem to encourage lateral growth. This technique also helps ensure the secondary branches receive light more evenly.
• Flowering: Flowering is truly impressive, with the plant developing a generous amount of long pistils that give way to dense, pyramidal buds that fatten up quickly. These buds should be well-fed throughout flowering to prevent nutrient deficiencies, as this purple weed strain handles high doses of fertilizer very well. It’s a spectacular sight when the plant begins shifting from green to a deep purple hue across its leaves and calyxes.
  • Another standout feature is the intense trichome production. The swollen calyxes become coated in large resin heads, while the surrounding leaves are covered in a frosty layer of crystalline trichomes.
• Aromas: The aromas are truly delightful and intoxicating, filling the palate with a sweet, spicy, and fresh profile. On the exhale, you’ll notice a strong citrus and fruity retro-nasal finish. The effect hits quickly, bringing on a deep sense of physical and mental relaxation.

Red Strawberry Banana Auto®: Seasonal Fruits

This purple cannabis strain from Sweet Seeds® can be seen as the spiritual successor to the legendary Red Poison Auto® (SWS39). In fact, it’s the result of crossing an elite Strawberry Banana clone with a carefully selected genetic line of Red Poison Auto®.

Red Strawberry Banana Auto® is incredibly easy to grow and finishes ultra-fast. It’s a perfect choice for beginners looking for quality and a harvest in record time, as it can be ready to chop just 7 to 8 weeks after germination.

Its speed and ease make it an excellent option for continuous outdoor harvests or intensive indoor grows. When grown indoors using organic methods and high-end LED lighting, the results are truly outstanding in terms of yield, resin production and organoleptic qualities.

This purple weed strain thrives indoors and quickly shows off its Indica-dominant traits through compact growth and massive leaves. It’s also light on nutrient demands, so the feedings should be kept mild, as this plant doesn’t require a high EC to produce dense, healthy flowers.

Red Strawberry Banana Auto® Through the Flowering Stage

Once Red Strawberry Banana Auto® enters the flowering stage, it kicks into high gear with fast and abundant bud development. We recommend using a good bloom booster early on to take advantage of this vigorous first push.

Keep in mind this is a very fast strain, so it’s important to avoid overfeeding it after the sixth week from germination. Pay close attention: once the first pistils start to fade, you might have just 10 days left before harvest.

Its buds are round, spaced out, and incredibly dense and hard. The red-purple coloration gradually spreads throughout the plant and becomes even more intense during the root flush.

You’ll notice the calyxes are huge, so be patient and let them swell fully. The reward? A top-tier purple cannabis strain bursting with potency, resin, and bag appeal. Even at a glance, the thick coating of glistening trichomes is impressive.

Sweet and Fruity Aromas from Red Strawberry Banana Auto®

The aroma of fresh Red Strawberry Banana Auto® is fruity and candy-like, with subtle hints of nuts and herbal notes reminiscent of arugula.

It’s an incredibly flavorful and aromatic strain with a long-lasting taste that makes every puff or vape session a pleasure from start to finish. The effects are relaxing, creativity-enhancing, and great for sparking the imagination.

With these five stunning purple cannabis strains from Sweet Seeds®, we wrap up this roundup… Until next time! Don’t forget to check out the Sweet Seeds® catalog to find the perfect strain for your next grow or genetic collection.

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Sweet Seeds S.L. is not responsible for any misuse of the information provided in this article. Growing Cannabis may constitute a criminal offense or administrative infraction; please check the Cannabis legislation applicable in your place of residence. Sweet Seeds S.L. does not, under any circumstances, intend to promote illegal practices.