Get local results

 Current general location:  
Enter your location to see results closest to you.
We do not share your location with anyone.

What Cannabis Strain Has the Most THC, According to Lab Data?

October 30, 2017

The last several decades of cannabis breeding generated thousands upon thousands of strains, many with high levels of THC. This begs the question, “Which strain has the most THC?”

The answer, according to numbers pulled from Washington state’s I-502 data, might be Ghost OG. (Leafly filtered the data to remove suspicious outliers and avoid labs that may have inflated THC values.)

What is THC (Tetrahydrocannabinol)?

About Ghost OG

Ghost OG is a hybrid strain with a mysterious origin story likely written only on the ancient walls of an online growing forum. However, it’s said to be a cut of the original OG Kush passed along from one breeder, ORGNKID, to another named “Ghost.”

Find Ghost OG Nearby

While its history is known by few, the name is known by many, preserved by a reputation built on numerous Cannabis Cup awards. Wearing a thick white sheet of crystal trichomes, Ghost OG can produce a predatory amount of resin best reserved for fearless cannabis heavyweights. Skillful gardeners can coerce loud aromas from this strain that reek of acrid lemon-pine cleaner and deep earthy goodness. Coveted Ghost OG genetics have been used to breed several other strain staples like Ghost Train Haze, Rare Dankness #1, and Banana Kush.

What Are You Smoking? Episode 12: Josh D and the Real OG Kush Story

How Much THC Does Ghost OG Have?

Advances in cannabis lab testing have helped to put the terms like “strength” and “potency” in quantifiable terms—a percentage point that many consumers now primarily look to when choosing a strain. Though we now know that a strain’s subjective intensity is determined by a harmony of cannabinoids and terpenes, many people primarily focus on the THC content if looking for a powerful cannabis experience.

Cannabis Potency: How Does Lab Testing for THC and CBD Work?

Through genetic selection and advancements in growing technology, cannabis plants can now produce over 25% THC by dry weight—a substantial increase from the single-digit figures strains touted in decades past.

Ghost OG’s average THC content, according to lab data, pushes past 28%, the highest figure in the dataset. Compare that to the average THC content of these popular strains:


THC levels: Ghost OG vs. the most-viewed cannabis strains on Leafly

Click to enlarge. (Amy Phung/Leafly)

If cut from the original OG Kush mother stock, why is Ghost OG’s average THC percentage so much higher? Could it be that these prized Ghost genetics fell into the hands of particularly talented propagators and cultivators, while the potency score of the widely proliferated “generic” OG Kush was skewed by more lackluster samples?

Factors That Impact Your Cannabis Strain: Part 3, Growing Techniques

Several other cannabis strains in our dataset fell slightly short of Ghost OG’s average THC content:

Click to enlarge. (Amy Phung/Leafly)

Many of these runner-ups are cut from the same genetic cloth as Ghost OG with deep OG ancestry, but somewhere along the way, Ghost OG held its edge.

But I’ve Seen Plenty of Flower With More THC. What Gives?

It’s plausible you’ve come across strains that exceed the 28% THC benchmark. Given these figures are an average of measured THC profiles, it makes sense that you’d find individual samples on either end of the high-low spectrum.

Consider also the credibility of cannabis testing labs and the possibility of THC inflation. Earlier this year in Washington state, for example, some labs were suspected of artificially inflating THC profiles to make clients’ samples appear more potent, perhaps to give them a competitive edge over other labs. Again, the dataset used here excludes questionable data sources.

Washington Labs Launch Effort to Address Credibility Crisis

Keep in mind the biological limits of THC production. This chemical ceiling rests somewhere around 30% or so THC by dry weight, and if you see any strains pushing far past that, you have every reason to be skeptical.

The question of which strain packs the most THC in a single flower will almost certainly be a matter of ongoing debate as more data is collected and assessed. For now, it’s clear that Ghost OG stands out among the resin-packed queens of 2017, but which varieties will ascend to the throne next?

Find Ghost OG Nearby

Bailey Rahn's Bio Image
Bailey Rahn

Bailey is a senior content manager at Leafly, specializing in strains and health. She's spent 7+ years researching cannabis products, spreading patients’ stories, and exploring healthy ways of integrating cannabis into daily life.

View Bailey Rahn's articles