Each year cannabis gets more potent, now with many strains reaching up to astronomical THC levels around the 30% mark. Finding these strains can be tricky but are worth every moment once you do. From their flavor to the superb high they deliver, these wonderful genetics will surely keep you satisfied on the bud front. We're back with another top strains article that focuses solely on one thing: high THC content.
This very powerful hybrid called Royal Gorilla was first only available in the US. With very high THC levels that go up to 27%, this lady will give an amazing high of vast relaxation together with a balanced feeling of euphoria. Because she is so potent, it is a strain with the good medical potential to help patients with chronic pains and others.
It does not give the biggest yields because this is a strain where quality goes over quantity! She is capable of growing in and outdoors where she will grow massive buds under a carpet of lime-green leaves.
Barney's Farm has been killing it when it comes to keeping up with new trends in the cannabis cultivation space. Runtz Muffin (Zkittlez x Gelato) is one of their recent releases and does not disappoint in the slightest. This juicy lady spills over with THC (up to 29%), developing tight nugs during flowering that can display a whole range of deep purples and vibrant greens and oranges.
The members of GrowDiaries have eagerly started experimenting with Runtz Muffin, with growers such as happygrower1 satisfied with the harvests and quality of the bud, stating 'I can't speak highly enough of Runtz Muffin'. This strain we can definitely see becoming a widespread favorite and is well recommended for those who love citrusy flowers.
There are many versions of the Chemdog (OG Kush x Sour Diesel) strain, but Anesia Seeds has earned the title for producing one of the strongest varieties. This green girl has produced up to a whopping 32% THC in previous tests, which makes it one of the top in its category.
Chemdog is a mostly Sativa hybrid and flowering can be completed in around 10 weeks. Have a look a Mosio's diary, who recently finished an outdoor grow and reaped some nice yields from a Chemdog plant. Topping and LST can help this stretchy sativa stay short, while making sure to give her plenty of sunlight.
This fire plant by OG Raskal won second place at the High Times Cannabis Cup in 2017. Although a few years old now, White Fire OG (also sometimes called WiFi) still ranks as one of the higher THC strains in existence. An excellent choice for breeders looking for powerful genetics.
White Fire OG Raskal seeds are another rare occurrence, however, Growers Choice also offers a version of White Fire OG (up to 28% THC) on their strains list. For those looking to get a taste of this fiery flower, this may be your best option, unless you can find it available for purchase somewhere.
Bruce Banner #3 is a powerful strain originally created by Dark Horse Genetics. As an OG Kush x Strawberry Diesel hybrid, the flowers grow to be extremely trichome-dense, giving off a pungent chemical, gassy, earthy odor that can draw any keen cannabis consumer in for a hit.
Bruce Banner #3 was once one of the strongest strains in the world, according to the High Times Cannabis Cup, but original seeds are quite hard to come by these days. The Dark Horse Genetics strain is quite old now but remains to be relevant due to all the descendants that have come from it. Original Sensible Seeds have created their own variety (Colorado Ghost OG x Strawberry Diesel), which has proved itself as a top, THC loaded strain.
Many growers continue to enjoy Bruce Banner, and it has become a popular choice among GrowDiaries users:
The result of a lovechild crossed out of two legendary strains ( Girl Scout Cookie X Gelato 33 ). She has the right genes for great potent flowers with a sweet taste and an impressive yield!
After flowering for 8–10 weeks, she produces approximately 600g/m² when cultivated indoors! Growers can enhance yields through training techniques such as LST and when done right the potency levels go all the way up to 28%!
Humboldt Seeds is now one of the biggest players in the seed breeding scene. The New is a collaboration between Humboldt Seed Organisation and pro cannabis breeder Sherbinski (Mario Guzman), creator of strains such as Gelato or Sunset Sherbert. The New derives from two tasty parents, Girl Scout Cookies and Larry OG, with the end result being an indica dominant monster.
She might not be the 'strongest' in this category, but The New does reach levels close to 30% THC and is mega potent nonetheless, so it deserves to be included as a top strain. First seen about a year ago on GrowDiaries, The New has shown sparkling results this year and is 'by far the stinkiest plant I have ever grown', according to myk420, who recently harvested some awesome buds dripping with trichomes. See here:
Barney's Farm is back again but this time with a well-balanced hybrid called Mimosa Evo (Mimosa x Orange Punch). You just need to look at this plant to know it's coated in sticky goodness. THC levels can hit 30% at best with yields also being flavorish, at up to 700gr/m2 indoors. Under the right conditions, Mimosa Evo can turn out to be a real treasure.
Leaves can display all sorts of appealing purply colours through late flowering and the smell of the buds can be described as piney, citrusy with a tropical twist. Browse GrowDiaries to see how growers across the world are getting on with Mimosa Evo. The harvests are looking promising.
Future #1 (Gorilla Glue #4 x Starfighter F2) by Anesia Seeds is one of those strains that can consistently reach over 30% THC, and has in some cases even tested at over 35%. Future #1 can be considered to be up there with some of the strongest strains currently on the market.
Future #1 seems to respond well to stress training such as pruning, topping and defoliation, amongst others. In addition, she does not require heavy feeding schedules to reach her full potential and can be grown in either soil or hydroponics. If you're interested to see more about Future #1, why not head over to Silky_smooth's grow diary from earlier this year:
The Toad (Chemdawg OG x Girl Scout Cookies) is an Indica dominant strain exclusively available through Mike Tyson's brand called Tyson Ranch. THC levels are said to reach between 31-37%, and the buds have an aromatic smell similar to diesel, oranges and cinnamon.
It seems seeds are not available for purchase anywhere and the Tyson Ranch products can only be bought in California and Nevada. Let's see if this strain makes its way to breeders across the world so home growers can start experimenting. If you've had the chance to try The Toad, feel free to leave your review down in the comments section!
We hope you find new highs in this list of top strains for 2021. Stoners will continue to seek fresh flavours and as their tolerance grows, more THC. Whether cannabis can keep getting juicier in cannabinoids is for the future to decide, but +/- 30% THC strains should be more than enough to keep most cannabis consumers satisfied.
Strain |
Indica/Sativa |
Flowering Time |
THC |
Royal Gorilla ( Royal Queen Seeds ) |
50/50 |
8 - 10 weeks |
Up to 27% |
Runtz Muffin (Barney's Farm) |
70/30 |
56 - 63 days |
Up to 29% |
Chemdog (Anesia) |
25/75 |
9 - 10 weeks |
Up to 32% |
White Fire OG (OG Raskal) |
40/60 |
60 - 70 days |
Up to 29% |
Bruce Banner #3 (Original Sensible Seeds) |
35/65 |
70 days |
25 - 29% |
Cookies Gelato ( Royal Queen Seeds ) |
50/50 |
8 - 9 weeks |
Up to 28% |
The New (Humboldt Seeds) |
80/20 |
65 - 70 days |
Up to 28% |
Mimosa Evo (Barney's Farm) |
60/40 |
65 - 70 days |
Up to 30% |
Future #1 (Anesia Seeds |
50/50 |
9 - 10 weeks |
30% - 37% |
The Toad (Tyson Ranch) |
60/40 |
Unknown |
31% - 37% |
-- White Fire OG | PSI Labs - Accessed 02.12.2020
The Toad (84) - Tyson Ranch | Proper (aproperhigh.com) - Acessed 28.12.2020
Cannaconnection - Royal Gorilla
Royal Gorilla - Royal Queen Seeds
This article was updated April 2021.