What is a high amount of THC for cannabis?

What is a high amount of THC for cannabis?

Many cannabis lovers are curious to know what is considered a high amount of THC in cannabis. With so much buzz about 30%+ THC strains you may be surprised to know that the average THC levels of the most popular cannabis seed varieties bought in Dutch coffee shops is around 16%. But what about the premium Dutch coffee shop strains? How much THC is in average hash? Read on to find out all you need to know about THC in your favourite cannabis products.

What is considered a high amount of THC in weed?
Does the amount of THC determine how high you'll get?
How does THC make you high?
How to measure THC potency at home
How to increase THC levels when growing cannabis
Discover our best High THC Cannabis Seeds

What is considered a high amount of THC in weed?

Cannabis consumers are often mislead into thinking that any cannabis strain with under 25% THC must be noticeably less potent than average. Yet much of the cannabis grown and consumed is around 16% THC. In The Netherlands the Trimbos Institute conduct an annual survey of cannabis and hash potency. Trimbos are the Dutch Institute of Mental Health and Addiction.

The 20th annual survey has just been completed, with cannabis samples purchased from 49 different coffee shops. In each case, the strongest cannabis variety was purchased from the coffeeshop as well as the most popular variety. THC and CBD are measured. What makes the Trimbos study so informative is the scientific way the information is gathered.

You may be interested to know the THC levels in the very best ‘premium’ coffee shop weed varieties was 18.4%. So from that evidence alone, you could say that around 18% THC is considered a high amount of THC in weed. After all, the Dutch coffee shop system has been established for several decades. Many coffee shops are supplied by skilled professional growers using reliable genetics. Yet many people would perhaps have expected the best coffee shop strains to contain well over 20% THC.

Coffeeshop THC average level

For comparison the most popular (best selling) coffee shop varieties had THC levels of 16.7%. The difference between the popular coffee shop strains and the premium strains was just 1.7% THC. Hash lovers may be surprised to find that the average THC levels found in Dutch coffeeshop hash was just 26%. That’s just 7.4% stronger than the premium weed strains.

Full Trimbos cannabis survey (Dutch language only)

These THC values from the Trimbos institute are very similar to those found in the UK. A survey from the UK Home Office showed median THC levels of 15.0% in samples seized by the police. Virtually all UK cannabis is UK grown, very little is imported. The UK Home office survey is here. The 15% average THC levels found in the UK are similar to the 16.7% levels seen in popular Dutch coffee shop strains. That suggests that high amounts of THC in UK weed would also be likely in the range 16-18% THC.

THC Levels guide on Dutch Passion


THC Percentage


0 - 5%


5 - 10 %


10 - 15 %

Very high

15 - 20 %

Extremely high

> 20%

What are the highest THC percentages in weed to date

It’s rare to see THC levels above 25%. Although it is far more common to see claims of 25-30% THC levels in pot. Usually, the very finest quality cannabis you will see is in the range 25%-30% THC. In the real world, any cannabis strain with over 20% THC should be considered very strong. In general it’s good advice to expect extravagant THC claims to be backed up by lab data, most of the time it isn't.

Dutch Passion use independent laboratories to conduct THC testing, usually two different labs are used and the data is compared. By using independent labs the data is likely to be more accurate than the potentially biased data you can get from tests made yourself. By using two independent labs you eliminate the chance of rogue results. The highest THC levels seen by Dutch passion in an autoflower strain was 25.9% in Auto Cinderella Jack.

Auto Cinderella Jack THC XXL

Professional cannabinoids lab analysis of our Auto Cinderella Jack:

Professional cannabinoids lab analysis of our Auto Cinderella Jack:

Does the amount of THC determine how high you'll get?

Not necessarily. Other factors can affect the type of high and the intensity you feel. The presence of cannabinoids other than THC can have a large effect on the type of high that you experience. Many cannabis connoisseurs enjoy strains with a cannabinoid profile which contains more than just THC. The entourage effect is the name given to the synergy of several cannabinoids acting together to amplify the effects/pleasure of the high. Often this will mean the cannabinoid profile may show small amounts of CBD, CBG, THCV, CBC, CBN and others.

In addition to the entourage effect from other cannabinoids, it is thought that the terpene profile also plays a large role in modulating (or ‘steering’) the type of high we experience. That’s why cannabis connoisseurs place such a large emphasis on the harvesting, drying and curing of their cannabis.

One other consideration is your own personal taste. Indica lovers may prefer their favourite indica strain rather than a more potent sativa. Perhaps it’s less important to ask which variety will get you the most high, and more important to ask which strain you will enjoy the most. For some people that could be a medium level THC strain with some CBD, for example. The highest THC strains are not necessarily the ones which you will enjoy the most.

All you need to know about cannabis terpenes

Amount of THC it takes to get high

The amount of THC you need to get high varies from one person to the next, depending on your tolerance. An inexperienced cannabis user might get very high from vaping weed containing 5-10mg of THC. A more experienced user might be able to take 5 times that, or more.

If you were eating a cannabis edible, an experienced user might be able to take around a gram of oil. That’s around 700mg of THC, considerably more than a novice user should ever consider using. One contentious area in countries with legal cannabis is around the strength and labelling of cannabis edibles. Some people are worried that cannabis edibles can be too strong for the unwary consumer and want to set THC limits. Others are worried that some edibles look too much like children’s candy. One consideration when consuming a high THC edible is that the high may not reach it’s peak for a couple of hours. During that time, it’s important not to continue eating more edibles.

Auto Cinderella Jack THC frosty buds

How does THC make you high?

A complicated biochemical process called pharmacokinetics is responsible for the absorption, distribution, metabolism and elimination of THC in the body. Once in the body, THC interacts with the human endo cannabinoid system. Specific receptors bind with the THC, particularly the CB1 receptors which are designed for exclusively for cannabinoids.

The discovery of the endocannabinoid system in the 1990’s was quite a breakthrough in understanding the way cannabinoids are used by the body. Even today, researchers are still only scratching the surface of cannabinoid science and cannabinoid medicine. Much still remains to be learnt about the way THC affects the body and rewards the mind with so much pleasure. It does all this with a uniquely diverse range of medical benefits and so few side effects.

High potency THC effects

For experienced cannabis users, the effects from consuming a large amount of a highly potent, THC rich strain may feel slightly disorienting, but nevertheless delightfully pleasant. The seasoned cannabis user is often more used to the effects of THC than the occasional user, and less likely to feel panicked or anxious after using a large quantity. In fact, many regular cannabis users feel that a big hit is one of the better ways to kick back and relax.

The psychoactive effects feel powerful after a large THC hit. You may feel like lying down, relaxing with TV, music or friends. Some people get a raging appetite after a particularly heavy THC hit. Many users experience an initial rush of euphoria, followed by a pleasurable sense of well being. The whole experience may last for several hours.

Depending on the cannabis strain you are using you may feel more restful and even wish to take a nap. Conversely, some people prefer to go out clubbing. Everyone is different, with a unique endocannabinoid system. Different individuals may feel quite different effects even when given the same amount of THC.

Best 5 THC rich cannabis seeds from the USA

Store your weed in a jar

How to get best THC potency

Whether you are growing a small number of plants at home, or doing it on a more professional scale, everyone wants to optimise their grow room conditions and harvest quality. One way to make a step-increase in quality levels is to grow with a quality LED growlight from an established vendor. Upgrading to LED is one of the most expensive grow room upgrades you will ever make. But it will also be one of your most important and one you won’t regret.

Many professional growers have compared LED directly against HPS using identical clones. Clones grown under LED shows superior THC levels to those grown under HPS. THC levels of around 17% under HPS may increase to around 23% under LED. Add a UVB grow light to your grow room if you really want to push the genetics and increase THC up another couple of percentage points.

Having the best cannabis seeds is also a key factor in getting the highest THC levels and best potency. If you use poor quality cannabis seeds you will never get a quality harvest no matter how optimised your groom is. Choose the best cannabis seeds you can from a seed company with a reputation that you can trust.

Grow experience counts for so much. Learning how to ensure the plants receive the correct nutrition, lighting and water throughout the grow takes time. The more you learn, the better you become.

How to grow cannabis indoors

How long does THC take to lose its potency

Cannabis stored in the freezer will remain potent for many years, probably a decade or more. Even cannabis which has been stored at room temperature and forgotten in a drawer for 3-4 years can be smoked and enjoyed with a good quality experience. The hotter the storage conditions the faster the THC will degrade. Of course, higher temperatures also cause the flavoursome terpenes to be lost. Light also degrades THC, turning it into CBN. For that reason it’s always good practice to store your buds in a dark place, never in a jar placed in direct sunlight.

How to measure THC potency at home

Unfortunately, so far there is no low cost, repeatable and reliable way to measure THC levels in your buds at home. Many low cost analysis devices have come and gone over the years. There have also been sensors which connect to smart phones which claim to be able to measure THC potency simply, cheaply, repeatably and accurately. Unfortunately none of these devices are reliable. Dutch Passion have seen and tested many of them over the years.

The best way to measure THC levels is to use a professional analytical laboratory. Unfortunately it’s also expensive and can cost well over €100 to get cannabinoids and terpenes measured. This is a necessary expense for professional cannabis seedbanks and licensed cannabis producers. But few home growers can afford the privilege.

How to test THC potency in buds

Methods such as TLC (thin layer chromatography) can be used to give approximate results without the need for expensive analytical equipment. But the most accurate results come from professional chemistry labs equipped with High Pressure Liquid Chromatography (HPLC) machines. These can measure precise quantities of cannabinoids, accurate to one or two decimal places.

Amber milky clear cannabis trichomes

What to look for during peak THC potency

During cannabis cultivation many growers will harvest at a point determined by the trichome appearance. The precise harvest time depends on your personal taste. Some prefer to harvest early while all the trichomes are clear, for an energetic buzzing high. Others prefer a heavier stone, perhaps harvesting when they see many of the trichomes becoming amber coloured. Perhaps more usual is the tendency to harvest at some point in the middle when the trichomes are mainly cloudy.

Do you lose potency from THC when making cannabutter and edibles?

One danger from cooking with cannabis (or cannabis extracts such as canna butter, cannabis oil etc) is overheating/overcooking the edible and allowing excess heat to degrade some of the THC. Anyone using a frying pan for making edibles, for example, will have less control over the maximum achieved temperatures than a thermostatically controlled oven. THC is reasonably stable when making edibles. But if you subject the THC to prolonged periods of high temperatures (e.g. 250ºC) you can expect to see potency degrade. But follow a proven recipe using a lower oven temperature and you should be fine.

How to increase THC levels when growing cannabis

THC levels are not magic numbers

One common question from growers is ‘how do I increase THC levels in my grow?’. As grower experience increases (there are no short cuts here unfortunately!) the ability to understand and care for the plants improves. So do the results and harvest quality.

Note that Dutch Passion label the varieties according to the potency potential of the genetics. In good conditions you will get very high THC levels from one of the Dutch Passion very high THC strains. However it is important to state that without good grow conditions the plants will simply fail to reach their full potential and you will get low THC results.

If you are serious about improving your grow skills and want to learn some useful grow tips and advice this blog may be useful reading.

How to optimise your grow room conditions
Growing cannabis indoors

Some of the easiest ways to improve THC levels and plant health are to consider a few grow room upgrades:

  • Quality LED grow lights, when used correctly, will allow you to take your quality up to the next level
  • Use of air-pots or felt grow bags improves root aeration and plant health
  • Consider UVB light supplementation during bloom to increase THC levels
  • Identify and eliminate sources of plant stress in your grow room
  • Improve your own knowledge with online reading, books etc

Remember, it’s up to you to bring out the full genetic potential in your plants by optimising the grow conditions and environment. There is limited purpose buying the best cannabis seeds and expecting the highest THC levels if your grow room needs obvious improvement.

Learn as much as you can about plant nutrition, lighting, optimised temperatures, air movement, humidity, plant stress reduction etc to bring out the best from the cannabis seeds you grow. Soon you will be a Master At Work!

Three high THC varieties from Dutch Passion

Discover our best High THC Cannabis Seeds

Remember that not everyone finds that the most pleasurable strains are the strongest ones. Some people love to grow crop after crop of 20-25% THC crops. Whereas other people can find the effects from these high THC strains a little too over whelming and prefer a medium strength THC strain, or perhaps one with CBD present.

But if growing the strongest strains with maximum THC values is your thing, you need to check out Dutch Passion’s elite collection of extremely high THC strains. These feminised seeds and autoflower seeds are all capable of delivering well over 20% THC. In optimised conditions you may be one of the lucky people to exceed 25% THC with some of these powerful cannabis seeds.

If you can sometimes feel a little overwhelmed by the highest THC strains, then feel free to play with Dutch Passion’s filters on our webshop. You can choose low THC seeds, medium THC seeds, or seeds which will deliver the highest possible THC levels.

What is a high amount of THC for cannabis?
May 1st 2020

Leave a comment


Jay - Dutch Passion

2021-07-21 11:27:23

Hello @ Robert O Lewis 2021-07-18 03:53:36 THCA and THC are 2 different molecules. Consuming THC will get you high even if you do not heat it. THCA is the precursor of THC, consuming THCA without heat will not get you high. If you heat THCA or you expose it to sunlight, it converts to THC. THCA loses its acidic carbonyl group to become THC. Hope this helps! Greetings, Jay Dutch Passion

Robert O Lewis

2021-07-18 03:53:36

Please tell me the difference between THC and THCA. If you have high %'s of THCA is that the same as high %'s of THC

Jay - Dutch Passion

2021-05-04 12:43:17

Hey @ Red 2021-04-29 23:50:32 If you mix those 2 with each other you will get an average of 13% thc in your mixed bag :) Greetings, Jay - Dutch Passion


2021-04-29 23:50:32

If you added cannabis having a thc level of 10 with cannabis having 16 thc, would it increase the thc to 26? Or lower it to 13?


2020-07-30 12:15:22

Tom, 20 mei 2020. Daar hebben we geen harde gegevens van aangezien de geteste soorten van binnen komen. Over het algemeen vallen de resultaten van buiten net iets lager uit omdat de omstandigheden vaak net wat minder optimaal zijn dan bij een gecontroleerde binnen grow. De kwaliteit komt van 1) de genetica 2) het licht en 3) de kweekomstandigheden.


2020-05-20 20:25:50

En wat met buiten wiet? De autoflowers die een zeer goede zomer hebben in Nederland? Zijn daar gegevens van?