Top 15 Strongest Weed Strains (High THC Strains) - UPDATED

Cannabis varieties Growing

Cannabis is getting stronger thanks to growing trends for high-potency THC strains. As we begin to genetically mix our very best cultivars, we uncover stronger and more stable combinations. So, whether you’re after a long and listless Sunday high or looking to energize and inspire, here are the top 15 strongest strains to choose from. All are fantastic for those seeking a serious high that won’t dissipate anytime soon.

What is the strongest strain of weed?

Living up to its name as a true Don of strong cannabis, Godfather OG is the most potent strain. It contains THC levels of up to 30% and is a multiple award winner as well as a record-breaker. What’s more, as this is an average activated THC content, it can push well beyond 30% with high-quality cultivation techniques.

Strong, potent and high in THC: why are these strains popular?

Strong and powerful high-THC strains have become the go-to option for cannabis connoisseurs and are among the top-selling varieties available today. Back in the 1990s, you could expect cannabis to average around 4 to 10% in THC. Right now, that’s tripled, with strains regularly pushing 20% and even more.

One of the clearest reasons for this rise is consumer demand. Stronger strains provide more long-lasting effects, making them ideal for medicinal users treating chronic or acute conditions. Recreational users want these top-dollar experiences too, offering more intense, euphoric and relaxing highs, depending on the particular strain genetics.

This has all been met by a revolution in cannabis growing culture. Cultivation methods have gotten better and new insights, like light exposure manipulation, lead to stronger strains. High THC cannabis is only going to get more popular for those in search of a bigger high – just be sure to watch your dose if you’re used to those old, 1990s-style strains!

Top 15 Strongest Weed strains

  1. Godfather OG – Highest THC strain 2021
  2. Ghost Train Haze – Highest THC strain 2020
  3. Chiquita Banana – Highest THC strain 2019
  4. Berner Cookies – Highest THC strain 2018
  5. Bruce Banner – Highest THC strain 2017
  6. Sirius Black – Highest THC strain 2016
  7. Gorilla Glue #4 – Highest THC strain 2015
  8. Gelato – Highest THC strain 2014
  9. Zkittlez
  10. Doug’s Varin
  11. Granddaddy Purple
  12. Girl Scout Cookies
  13. Acapulco Gold
  14. Pure Power Plant
  15. Big Bud

1. Godfather OG – Highest THC strain 2021
THC levels reach up 30%

The exact origins of Godfather OG are as shadowy as the mafia, and Godfather OG is as powerful as Brando’s Corleone. It is often labeled the Don of all Kush strains, and it is believed that Godfather OG is a cross between Alpha OG and OG Kush.

According to the High Times, Godfather OG is the strongest weed strain in the world currently available. To add to these accolades, it won the award for best Indica at the High Times Cannabis Cup in 2013.

Godfather OG’s THC percentage is typically 28% to 30%, but can reach a world-class 34%. This Indica-dominant weed is therefore incredibly strong. Known for its sleep-inducing properties, it produces an intense euphoric and cerebral effect accompanied by a physical impact of total relaxation – a trip not to be missed.

The smell and taste of Godfather OG is unique. You will taste a piney and earthy flavor with fruity undertones.

Growing

Godfather OG can yield up to 450 grams per m2 when grown indoors under ideal conditions. Outdoors, plants can yield up to 650 grams per m2. However, the flowering time is only 49 to 63 days. It is a great favorite among growers, partly because of its speed and resilience.

Effects

The high is incredibly strong, starting with a powerful cerebral high that leads to long-lasting sensations of relaxation.

Godfather OG is often used by patients with a range of chronic conditions. These include insomnia, depression, anxiety, chronic pain and many mental disorders.

Note: Godfather OG is powerful enough to deliver a knockout blow. Therefore, use the weed carefully and in a low dosage.

Godfather OG feminized seeds Godfather OG feminized seeds
Levels 30% THC / 0.8% CBD
Variety 60% Indica / 40% Sativa
Yield 350 to 650 grams/m²
Flowering time up to 49 days
Growersprofile Beginner

2. Ghost Train Haze – Highest THC strain 2020
THC levels reach up 30%

Ghost Train Haze, or GHT, is a powerful Sativa-dominant strain that boasts rich and dense crystal-covered buds loaded with potent THC. It can trace its origins to the much-loved and highly potent Ghost OG and Nevil’s Wreck.

Regularly appearing on strongest weed of the year lists, Ghost Train Haze has won numerous awards worldwide. She took the leading prize for best Sativa at the High Times Cannabis Cup in 2015.

Above all else, Ghost Train Haze is loved for its potency. Aside from impressive THC credentials, she holds a pungent and flavorful aroma that will fill the air with a sweet and floral scent. The effects are a classic mix of big cerebral and stimulating highs with blissful relaxation.

Growing

Ghost Train Haze isn’t a particularly easy strain to cultivate, and does much better in experienced hands. Under optimal conditions, you can expect to yield up to 700 grams per m2 outdoors! Not blessed by sun-drenched, Californian-like conditions? Indoors, you can expect to yield up to 600 grams per m2.

Effects

Ghost Train Haze lives up to its supernatural and inquisitive name by promoting big cerebral highs. These somewhat psychedelic bursts of creative energy are long-lasting and accompanied by a more Indica-like relaxation. Perfect for parties and gatherings, just be sure to watch your dose if your THC tolerance levels are low.

Ghost Train Haze feminized seeds Ghost Train Haze feminized seeds
Levels 30% THC / 0.2% CBD
Variety 20% Indica / 80% Sativa
Yield 400 to 700 grams/m²
Flowering time up to 63 days
Growersprofile Moderate

3. Chiquita Banana – Highest THC strain 2019
THC levels reach up 29%

Chiquita Banana is a predominant Sativa hybrid with a high THC content of 25% on average. However, her THC level can reach up to 29% and is therefore considerably strong!

At the Cannabis Cup in Northern California in 2015, she finished in third place of the best hybrid strains. She is deliciously sweet and has something akin to the taste of Banana Kush about her.

Growing

Chiquita Banana likes to be grown both indoors and outdoors. Indoors, the plant is capable of yielding up to 400 grams per m2. When grown outdoors, her yield can reach up to 600 grams per m2. These high yields can be achieved by novices and experts alike, as Chiquita Banana is easy to grow in the right warm and sun-kissed conditions.

Effects

As you would expect from a Sativa dominant high THC strain, the effect is powerful and energetic. Most recreational users admire this strain’s sociable and talkative qualities; the perfect party pick me up.

Chiquita Banana feminized seeds Chiquita Banana feminized seeds
Levels 29% THC / 0.5% CBD
Variety 40% Indica / 60% Sativa
Yield 300 to 600 grams/m²
Flowering time up to 56 days
Growersprofile Beginner

4. Berner’s Cookies – Highest THC strain 2018
THC levels reach up 27%

A modern Sativa-heavy classic, Berner’s Cookies is derived from the much-lauded Girl Scout Cookies. Just like that exquisite and sweet strain, it boasts a luscious flavor profile with a boosted THC content of up to 27%

Berner’s Cookies comes from the rapper and cannabis developer Gilbert Millam Jr. (or Berner), a mainstay of the San Francisco scene and friend of Wiz Khalifa. He developed this strain to be bold, sweet and, most importantly, super potent. Something to match with a rip-roaring DJ set or to begin an after-party.

Growing

Berner’s Cookies needs some care when growing, with regular maintenance of stems and leaves to ensure adequate light absorption. Under correct conditions, she produced bountiful harvests of up to 700 grams per m2 outdoors. Indoor growth can be kept under control with pruning, offering yields of up to 575 grams per m2.

Effects

Coming from a long and strong line of Cookies-branded strains, Berner’s Cookies is renowned for its uplifting and cerebral high. These energetic effects are perfect for getting conversations going, or for treating ailments like chronic pain and fatigue.

Berner Cookies feminized seeds Berner Cookies feminized seeds
Levels 27% THC / 0.07% CBD
Variety 25% Indica / 75% Sativa
Yield 450 to 700 grams/m²
Flowering time up to 63 days
Growersprofile Moderate

5. Bruce Banner – Highest THC strain 2017
THC levels reach up 27%

Named after the Incredible Hulk, Bruce Banner is a must-have option in this top 15 list of the strongest cannabis strains. Big, green but with a sweeter side too, it’s a marvel of the cannabis world.

The newest version of Bruce Banner is a cross between Strawberry Diesel and OG Kush. Her purple-green buds have a deliciously sweet taste and are extremely potent. On average, the weed has 24% THC, but that can go up to 27%! A remarkably strong weed indeed.

Growing

When growing indoors, it is advisable to keep the humidity low to protect the buds from mold. Outdoors, it should be grown in light, well-drained soil. Beginners are recommended to purchase autoflowering seeds for an easier grow.

Effects

With such a high THC content, it should come as no surprise that Bruce Banner is one of the most powerful strains out there. It makes you feel focused, happy, creative and relaxed – perfect for inspiration or deep conversations.

Bruce Banner feminized seeds Bruce Banner feminized seeds
Levels 27% THC / 0.3% CBD
Variety 50% Indica / 50% Sativa
Yield 500 to 750 grams/m²
Flowering time up to 63 days
Growersprofile Moderate

6. Sirius Black – Highest THC strain 2016
THC levels reach up 25%

Sirius Black is an Indica dominant strain that was originally developed by The Oregon Breeders Group. It is a delightful weed with a strong aroma and taste of ruby red grapes.

Just as mysterious as the Harry Potter character, it’s beloved for its potent and flavorful profile. Just one hit could send you to the magical world of Hogwarts.

Growing

As the name suggests, Sirius Black’s leaves and buds are dark with magical purple hues. It has a velvety, mysterious quality to it, just like the Harry Potter character. She has medium mold resistance and is preferably grown in warm, dry climates. It is also a plant that you can easily put in a SOG (Sea of Green) setup, as long as you have good ventilation.

Effects

The effect of Sirius Black is uplifting with cerebral. She stimulates creativity, gives feelings of euphoria and often induces fits of laughter. The initial high is followed by deep sedation, relaxation and finally sleep.

These overwhelmingly strong and sedative properties make her an ideal treatment for insomniacs. Sirius Black is also commonly used for therapeutic purposes in treating inflammation, pain and seizures.

Tip: Given the 25% THC, it’s an incredibly powerful weed that should be taken in doses to avoid a couch-lock.

Sirius Black feminized seeds Sirius Black feminized seeds
Levels 25% THC / 0.05% CBD
Variety 70% Indica / 30% Sativa
Yield 300 to 650 grams/m²
Flowering time up to 63 days
Growersprofile Moderate

7. Gorilla Glue #4 – Highest THC strain 2015
THC levels reach up 25%

Often simplified as just GG4, Gorilla Glue #4 offers a heavy-handed high thanks to its massive THC content. Its Indica side is the perfect option for the end of a busy day when you just want to wash your stresses away. Yet as a hybrid, its Sativa effects help stimulate and energize – so you don’t have to stay glued to the couch.

GG4 has been awarded numerous accolades over the years, including first place positions in many Cannabis Cups. It keeps going from strength to strength, being among the world’s most sought-after strains right now.

The naming of Gorilla Glue #4 becomes evident as you grow. Its rich and heavy buds are covered in such a sticky, THC-laced resin that you’ll find it difficult to cut without the sharpest of scissors.

Growing

Gorilla Glue #4 is easy to grow and an ideal first-time option for those looking to cultivate a very potent strain. While both indoor and outdoor environments are fine, you can keep more of a handle of things with an indoor growing system. Hydroponic and nutrient-rich soil options are a great way to reap up to 600 grams per m2.

Effects

Gorilla Glue #4 is a big and potent strain that can hit fast and long. Offering a blend of euphoric and calming effects, it tends to lean more into bodily relaxation. The high THC content possesses strong psychoactive potential that’s best taken in smaller doses.

Gorilla Glue #4 feminized seeds Gorilla Glue #4 feminized seeds
Levels 25% THC / 1.5% CBD
Variety 50% Indica / 50% Sativa
Yield 450 to 750 grams/m²
Flowering time up to 53 days
Growersprofile Beginner

8. Gelato – Highest THC strain 2014
THC levels reach up 25%

Despite its sweet names and mouth-watering dessert-like flavor, Gelato packs a big THC punch of up to 25%. This is weighted by a wonderfully balanced high that’s perfect for medicinal and recreational users alike.

This excellent strain is an Indica-dominant hybrid with cerebral Sativa qualities too. Originating in San Francisco, it has garnered a reputation as one of the sweeter strains. In keeping with the Cookies strains on the West Coast, Gelato is rich, creamy and fruity.

Growing

Gelato is a dream to grow, but does require some trimming to keep space between branches. Suitable for both indoor and outdoor growing, Gelato thrives in warm and dry conditions. With a flowering time of between 8 and 9 weeks, you can expect yields of up to 450 grams (indoors) and 550 grams (outdoors) per m2.

Effects

Gelato boasts a balanced high with big euphoric effects and full-body relaxation. Known for its sudden onset, you can expect these feelings to be long-lasting. It’s widely regarded for its medicinal uses to numb pain and relax the muscles.

Gelato feminized seeds Gelato feminized seeds
Levels 25% THC / 0.5% CBD
Variety 60% Indica / 40% Sativa
Yield 350 to 550 grams/m²
Flowering time up to 56 days
Growersprofile Moderate

9. Zkittlez – Highest THC strain 2014
THC levels reach up 25%

Zkittlez is an Indica dominant strain with a high THC content that can reach up to 24%. With her sweet tropical flavors, she is an incredibly tasty weed, especially if you have a sweet tooth.

This colorful plant produces abundant amounts of terpenes that translate into a wide range of mouth-watering flavors. You can definitely ‘taste the rainbow’ with its multi-colored menu of pineapple, orange and lemon, interspersed with hints of blueberries.

Growing

Thanks to her forgiving and laid back nature, Zkittlez is generally a pleasure to grow, You can grow her indoors or outdoors, where she thrives if exposed to plenty of sunlight and water.

Effects

The weed offers physical relaxation and mental stress relief without the feeling of being nailed to the couch. Still, this is one for those seeking an end-of-day unwind, as it’s immensely calming and soothing.

Zkittlez feminized seeds Zkittlez feminized seeds
Levels 24% THC / 0.5% CBD
Variety 80% Indica / 20% Sativa
Yield 500 to 600 grams/m²
Flowering time up to 49 days
Growersprofile Moderate

10. Doug’s Varin
THC levels reach up 24%

Doug’s Varin is loaded with rare THCV, a kind of super-charged THC that’s fast-acting and cerebral. Among the most unique strains out there, it’s energizing, focusing and fairly short-term. Think of it as the cannabis equivalent of a fine shot of espresso.

Doug’s Varin originated in California and potential has a genetic backbone of Harlequin and Thai Stick. Everything else is a mystery with this outstanding strain, which has potentially the highest THCV levels around. This is all complemented by an incredible aroma of pine needles and sweet crushed lemon.

Growing

Doug’s Varin can handle both indoor and outdoor growing. As a Sativa variety, it needs warmth and sunlight in abundance. You’ll also need to provide adequate space, as this strain is known to top 200 cm. Due to its nutrient and growing requirements, this is one for growers with experience.

Effects

Doug’s Varin is renowned as a quick-acting, energizing hybrid. Balancing THC and THCV, it provides a big psychoactive element that can overwhelm the inexperienced. What’s more, Doug’s Varin works well as an appetite suppressor and as such shouldn’t be taken by those treating appetite loss.

Doug's Varin feminized seeds Doug's Varin feminized seeds
Levels 24% THC / 0.2% CBD
Variety Pure Sativa
Yield 275 to 450 grams/m²
Flowering time up to 70 days
Growersprofile Moderate

11. Granddaddy Purple
THC levels reach up 23%

Beautifully lush with bright indigo leaves, Granddaddy Purple is truly eye-catching. Popular due to its impressive THC levels, it’s renowned for its relaxing, Indica characteristics. It’s quickly gone from a Californian staple to a worldwide classic.

Granddaddy Purple has its roots in Skunk and Afghanistan. Known by multiple names, it was spearheaded by the medicinal cannabis advocate, Ken Estes. Estes cultivates world-recognized strains for their therapeutic value. Granddaddy Purple is no exception; it works wonders in treating stress, pain and insomnia.

Growing

Granddaddy Purple is fairly easy to cultivate, but does pose some challenges for beginners. That’s because it’s particularly picky about humidity. Keep things at 50% for the best results. Granddaddy Purple is also well suited for both indoor and outdoor growing, although warm conditions are favored.

Effects

Granddaddy Purple boasts a wonderfully soothing and blissful high that will relax the body all over. Perfect for treating chronic pain and stress, this relaxation is long-lasting and sedative thanks to its strong THC levels. Just be sure to take this at night rather than during the day, unless you want to be stuck to your bed.

Granddaddy Purple feminized seeds Granddaddy Purple feminized seeds
Levels 23% THC / 0.4% CBD
Variety 80% Indica / 20% Sativa
Yield 300 to 800 grams/m²
Flowering time up to 56 days
Growersprofile Beginner

12. Girl Scout Cookies
THC levels reach up 23%

With a name reminiscent of the cookies sold by small American scouts, this weed is very popular in the US. With a typical THC level of around 23%, Girl Scout Cookies has retained the physical characteristics of OG Kush, and the intoxicating scent of Durban Poison. This hybrid is impressively strong and completes its flowering in just 49 to 63 days.

Growing

Girl Scout Cookies is an Indica-dominant weed and responds well to training methods such as Sea of Green (SOG) and SCROG. The plant is easy to grow and therefore very suitable for both beginners and advanced growers.

Effects

For an innocent-sounding name, Girl Scout Cookies offers a surprisingly hard-hitting effect. The body-high gradually spreads through your body, leading to long-lasting feelings of relaxation. She possesses strong sedative properties, making her a perfect weed for sleeping.

Girl Scout Cookies feminized seeds Girl Scout Cookies feminized seeds
Levels 23% THC / 0.7% CBD
Variety 80% Indica / 20% Sativa
Yield 450 to 650 grams/m²
Flowering time up to 49 days
Growersprofile Beginner

13. Acapulco Gold
THC levels reach up 23%

With Acapulco Gold, you take a step back in time to the 60s. This legendary weed, with a very rich history, is incredibly strong and adored by all lovers of Sativa weed.

Growing

As the name suggests, Acapulco Gold thrives in a warm and humid climate. Just like you would find in the Mexican rainforest. This is somewhat difficult to reproduce when growing indoors. As such, we recommend Acapulco Gold to experienced growers looking to experiment with a classic strain.

Effects

Acapulco Gold is a legendarily strong weed with Mexican Sativa roots. She arouses strong and unmistakable feelings of happiness that can make you feel enlightened and refreshed. A wonderful “head-high”, just as you would expect from a Sativa.
This powerful Sativa is uplifting and evokes feelings of sociability. She is therefore excellent as a party starter or icebreaker. Acapulco Gold will lift your spirits and leave you in a long-lasting state of euphoria.

Acapulco Gold feminized seeds Acapulco Gold feminized seeds
Levels 23% THC / 0.7% CBD
Variety 20% Indica / 80% Sativa
Yield 350 to 575 grams/m²
Flowering time up to 63 days
Growersprofile Moderate

14. Pure Power Plant
THC levels reach up 22%

Never has a strain name been more to the point. Pure Power Plant is potent, powerful and a pure pleasure giver. Loaded with up to 22% THC, it’s a musky, citrus-flavored strain that boasts huge Sativa characteristics.

Growing

Pure Power Plant is a fine beginner strain thanks to her robust and forgiving nature. Thriving best in warm and dry outdoor conditions, she’s also suited to controlled indoor setups, where SCROG methods can be used to great effect. Her hybrid credentials make her easy to manage, compact and highly resistant to mold.

Effects

Pure Power Plant does exactly what it says on the tin; it delivers a high-potency high that’s well-balanced, energetic and euphoric. It’s perfect for those seeking full-body relaxation without being glued to their seat. This power is complemented by a unique and fruity flavor profile that dances on the tongue.

Pure Power Plant feminized seeds Pure Power Plant feminized seeds
Levels 22% THC / 0.8% CBD
Variety 40% Indica / 60% Sativa
Yield 450 to 700 grams/m²
Flowering time up to 50 days
Growersprofile Beginner

15. Big Bud
THC levels reach up 22%

Big Bud is very popular among commercial growers because of its incomparable amount of huge buds. But that’s not all. The weed is considerably strong and therefore deserves 15th place in this top 15 chart of the strongest strains.

Growing

Big Bud is an undemanding plant. She has a flowering time of 49 to 63 days, which makes her a fast bloomer. Grown outdoors, Big Bud prefers a dry Mediterranean climate to a wet, humid one. She can also be grown outside in temperate climates through warm summers, weather permitting.

Effects

Big Bud will lift your spirits and induce feelings of happiness and euphoria. She is Indica dominant, which results in a cerebral high that also leaves you feeling completely relaxed. By the way, you will love her earthy and piney flavors and aromas of spices.

Big Bud feminized seeds Big Bud feminized seeds
Levels 22% THC / 0.6% CBD
Variety 80% Indica / 20% Sativa
Yield 400 to 1000 grams/m²
Flowering time up to 49 days
Growersprofile Beginner

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