When you’re considering what seeds to buy in order to cultivate your own marijuana plants, you’ll need to know what you are looking to achieve in order to compare the different strains. For many growers, having a the best high THC seeds is tantamount to having an incredible plant. A word of caution though: high THC content which is quoted by seed sellers and growers is not always a given. Achieving a high THC content is highly dependent on the amount of care the plant gets during its growth, as well as the methods used to cultivate your plant. To get really great THC content you need to make sure you are aware of what requirements that particular plant has for nutrients, light and other factors to ensure it is grown healthily and happily.What is THC? To give it its correct name, Tetrahydrocannabinol (THC) is one of the many ingredients found in cannabis. It is the active chemical that gives you a sense of being ‘high’, and is one of the oldest hallucinogens known to man. There is historical evidence of THC being used as a herbal remedy as long ago as the first century AD and is still today understood to have various medical properties as well as being a recreational drug.A marijuana plant contains around sixty chemicals which can be classed as psychoactive. Out of all of them, the two which are recognized as being the most potent and effective are THC and CBD (Cannabidiol). There is some evidence to say that CBD in some way neutralizes or dilutes the effects of THC, so when looking for a good THC strain you might want to consider its potential CBD levels too.Medical marijuana Although still out for debate, there is a growing supply of anecdotal evidence demonstrating how marijuana can have medicinal properties for the user. Back in 2004, an FDA doctor speaking to congress on the topic of marijuana as a medicine stated that it could never be used as such due to the difficulties in testing active ingredients for safety and usefulness. He said that the wide variations in active ingredients from plant to plant made it too tricky to identify a ‘dosage’ as such, and therefore was unable to recommend it for medical uses.Visit our trusted friends at , We Think So! They have a wide assortment of vaporizers, dabs and pipes for all your cannabis needs.Top 10 THC Strains#1.OG Kush Feminized SeedsIndica18% THCLow#2.LSD Feminized SeedsIndica Dominant22% THCHigh#3.Sour Diesel FeminizedHybrid17-21% THCVery High#4.Pineapple Chunk Feminized SeedsIndica dominant20% THCVery High#5.Big Buddha Cheese Feminized SeedsIndica dominant20% THCVery high#6.Jack Herer Feminized SeedsSativa Dominant18-20% THCMedium#7.Satori Feminized SeedsSativa Dominant23-28% THC (crazy high!)Medium to high#8.Sannies Herijuana IBL Feminized SeedsIndica dominant25% THCMedium to high#9.Train Wreck Feminized SeedsSativa dominant15% THCMedium#10.AK 47 Feminized SeedsSativa dominant20%+ THCMedium However, the FDA has remained open to advice and scientific research into marijuana and other cannabinoids, and the recent decriminalization of marijuana for medical uses in some US states is evidence of the direction in which the pendulum is swinging.From the small number of scientific studies, as well as anecdotal evidence it has become clear that THC, as an active drug, can be used to treat some medical conditions with success. THC has been shown to have a positive effects such as:Pain reliefAppetite stimulation in anorexic patientsAntiemetic (stops nausea and vomiting)Treatment and prevention of glaucomaTreatment of epilepsyTreatment of asthmaPsychiatric treatment including bipolar disorder, social anxiety and depressionTreatment of autoimmune diseases There are many other reported incidents of THC providing a benefit to sufferers of a wide range of illnesses. If you are unwell, then you should always consult with a qualified medical practitioner for conventional treatment too, but if you are looking to optimize for high THC content for medical reasons, you may find this list useful.Looking for an alternative to grow tents and grow boxes? Check out our friends atTop 10 THC Strains#1 OG Kush - 18% THCBest for: Stress relief, chronic pain and migraines Depending on where you come from, OG can either mean ‘original gangster’ or ‘ocean grown’. Whichever name you prefer, this California originating strain is a heavy hitter in terms of THC content. Its neon green leaves and orangey red stigmas produce big popcorn shaped buds literally dripping with resin. With a heritage that is said to go back to the Hindu Kush strains from India and Afghanistan, is one of the most potent weeds around and has long lasting, relaxing effects.We have reviewed different OG Kush Strains:Regular OG KushCali Connection Tahoe OG KushReserva Privada OG Kush FeminizedType: IndicaHeight: MediumFlowering time: 8 weeksAwards won: Spannabis Cup 2010 (2nd)Yield: LowFeminized: YesAutoflowering: NoGrowth difficulty: ModerateTHC level: High, around 18%CBD level: Low, usually less than 0.5%#2 LSD - 22% THCBest for: Anxiety, PTSD, pain relief and anorexia The LSD weed strain is a potent contender from the experts over at . By crossing a classically high THC Skunk with an equally potent Mazar, have developed a hard hitting, knockout weed strain with phenomenal levels of THC. The yield is high, and with average THC content in excess of 22% and low CBD, this is one you should definitely consider if you’re aiming to optimize for THC.We have reviewed different LSD seeds strains:Regular LSD SeedsType: Indica dominantHeight: ShortFlowering time: 6 - 7 weeksAwards won: High Times Cup 2008 (3rd)Yield: HighFeminized: YesAutoflowering: NoGrowth difficulty: ModerateTHC level: Very high, in excess off 22%CBD level: Low, usually less than 1%#3 Sour Diesel - 17 to 21% THCBest for: Mood enhancing, treating depression, ADD / ADHD, bipolar disorder We love Sour D, and you will too once you’ve enjoyed its energizing, cerebral high and long lasting effects. The notable diesel like aroma gives way to a quick and powerful punch of THC that seems to last and last. The effects are mainly mood enhancing, although it does serve to relieve some milder pains and aches too. The plant is tall and thin, reaching up to 6 feet when grown indoors and yielding a very high crop of around 550g per m2 or more. The aroma, however, is strong, so if you’re looking for a stealthy grow you should give consideration to your ventilation and odor control.We have reviewed a couple of Sour Diesel strainsRegular Sour Diesel SeedsSuper Silver Sour Diesel Haze Seeds Type: HybridHeight: TallFlowering time: 10 weeks or moreAwards won: High Times Plant of the Year (2005)Yield: Very highFeminized: NoAutoflowering: NoGrowth difficulty: Easy to moderateTHC level: High average tests of 17% and up to 21%CBD level: Typically well under 1%#4 Pineapple Chunk - 20% THCBest for: Heavy stone, couch lock, treating pain, anxiety and stress Another wonder weed which deserves a mention for its unbelievable THC content is the inimitable . Insanely sweet and delectably sticky, this is one weed that delivers on taste and effect every time. cleverly crossed their popular Pineapple strain with their Cheese / Skunk #1 to produce something packed with flavor and insanely strong. THC is typically well over 20%, with 25% or more being claimed by some growers. Delivers a strong couch lock and a rewarding yield every time.We have reviewed a Pineapple strainsBarney's Farm Pineapple Express Autoflowering Feminized SeedsType: Indica dominantHeight: Medium to tallFlowering time: 8 weeksAwards won: NoneYield: Very highFeminized: Yes, onlyAutoflowering: NoGrowth difficulty: EasyTHC level: Very high, in excess of 20%CBD level: Medium to low, usually around 1.1%#5 Big Buddha Cheese - 20% THCBest for: Heavy stone, couch lock, treating pain, anxiety and stress Produced by Big Buddha Seeds in the UK, this stain is a totally unique and very interesting one to try. The producers crossed original Cheese weed with their own pure Afghani male, resulting in this amazing little plant that will simply knock your socks off. All the fragrance and flavor of the original Cheese are present, but with the generous yield and high THC content of the Afghani delivering an even better result. The high is uplifting and very long lasting, making Big Buddha Cheese a great investment for those looking for something a bit different.We have reviewed a couple of Cheese strainsBig Buddha – Bubble Cheese Feminized SeedsBig Buddha - Blue Cheese FeminizedBlue Cheese Cannabis SeedsGreen House - Cheese Feminized Marijuana SeedsL.A. Cheese Weed SeedsType: Indica dominantHeight: MediumFlowering time: 8 weeksAwards won: NoneYield: Very highFeminized: Yes, onlyAutoflowering: NoGrowth difficulty: EasyTHC level: Very high, in excess of 20%CBD level: Under 0.3%#6 Jack Herer - 18 to 20% THCBest for: Balanced high, treating depression and anxiety, relieving arthritis Acclaimed by many as one of your ‘bucket list’ weeds, Jack Herer is well known as being a stunning experience if you can get them to grow successfully. The smell and flavor pay a nice homage to both the Haze and Skunk lines in its ancestry, with earthy, piney tones mixed with fresh, peppery hints. The hit is fast and hard, very cerebral and with a comfortable, painkilling body stone that lasts for a generous time. The THC is high, although not as high as some at around 20% or so. The moderate amounts of CBD at 1.5% might put some off, but we feel it balances out the high and makes this a stunning all round product.We have reviewed a couple of Jack Herer strainsAdvanced Seeds – Auto Jack Herer SeedsAuto Jack Weed SeedsType: Sativa dominantHeight: TallFlowering time: 8 to 11 weeksAwards won: 14 in total, including 2 High Times Cups and 7 High Life CupsYield: MediumFeminized: YesAutoflowering: YesGrowth difficulty: ModerateTHC level: High, around 18 – 20%CBD level: Medium, around 1.5%#7 Satori - 23% to 28% THC (crazy high!)Best for: Creativity, concentration, depression, sleep disorders and novice growers A less well known strain from established producers, Mandala Seeds, Satori is incredibly potent and tests as having some of the highest THC levels of any plant on the planet right now. The highest recorded from this strain was in excess of 28%, although you’ll be aiming to achieve around 22 – 25% growing at home. These seeds are naturally resistant to spider mite, and grow strong and tall, making them easy to pack into rows to boost the yield. The effect is very cerebral and creative, with a long lasting relaxing effect that can help with sleep disorders and anxiety.Type: Sativa dominantHeight: TallFlowering time: 8 to 10 weeksAwards won:Yield: Medium to highFeminized: YesAutoflowering: NoGrowth difficulty: EasyTHC level: Very high, around 23% – 28%CBD level: Unknown#8 Sannies Herijuana IBL - 25% THCBest for: Very high potency, pain relief, insomnia, pest resistance This is a great strain for those looking for that extra punch that you probably haven’t seen in years. The THC content of Herijuana is reliably high, always in the region of 25%, which makes this a desirable plant from both the medical and recreational point of view. Indica dominant, this plant actually grows like a sativa in the early days, but when it comes to flowering time you’ll see the indica traits in full bloom. Because of its vigorous branching, this is a good contender for SCROG growing with success. Highly recommended for those who love a good, strong indica.Type: Indica dominantHeight: MediumFlowering time: 7 to 9 weeksAwards won:Yield: Medium to highFeminized: YesAutoflowering: NoGrowth difficulty: EasyTHC level: Very high, around 25%CBD level: Unknown#9 Train Wreck - 15% THCBest for: Functional high, pain relief from migraines and joint pain, treating insomnia For a long time this powerful strain was only available as a clone, but thanks to the boys over at Homegrown Fantaseeds, you can now grow the legendary TrainWreck direct from seed. It’s a sativa dominant strain, but the indica in its genetics helps to fill out the plant with semi dense buds and sizeable kolas. The hit is instant and straight to the head, with a long lasting mellow feeling that leaves you with a functional, lucid high.We have reviewed a Train Wreck strainsGreen House Train Wreck Feminized SeedsType: Sativa dominantHeight: Medium to tallFlowering time: 8 - 10 weeksAwards won: IC420 2009 (3rd)Yield: MediumFeminized: YesAutoflowering: NoGrowth difficulty: EasyTHC level: High, in excess of 15%CBD level: Low, between 0.5 – 0.8%#10 AK 47 - 20%+ THCBest for: Daytime use, pain management, relieving nausea, movement disorders A highly popular weed strain, AK47 has been designed to knock you on your ass with no holds barred. In testing, this strain consistently produces plants with over 20% THC, delivering a pleasantly strong cerebral high and treating all forms of pain with great success. Although a sativa led plant, one of the main attractions of AK-47 is its relatively short flowering time and shorter plant height, making it good for indoor grows and a faster than average turnaround.We have reviewed a couple of AK 47 strainsVision – AK 47 SeedsLowlife AK 47 Autoflowering Feminized Marijuana SeedsSerious AK47 Feminised Marijuana SeedsAutomatic AK47 x Auto Hindu KushCritical 47 Weed SeedsAdvanced Seeds – Auto Kaya 47 SeedsRoyal Queen – Royal AK SeedsRoyal Queen Royal AK Automatic Feminized SeedsType: Sativa dominantHeight: Medium to tallFlowering time: 8 to 9 weeksAwards won: High Times Cannabis Cup 2011 (3rd), Indica Cup (HTCC) 2003 (2nd)Yield: MediumFeminized: YesAutoflowering: NoGrowth difficulty: EasyTHC level: High, 20%+CBD level: Low, under 0.5%That is the current pick of the best of the best for high THC content. We’d love to hear from you about your own preferences for high THC seeds, so either leave a comment below or check out our forum to share your input with others.