White Ash: Myth or Not?

White Ash: Myth or Not?

The attentive cannabis-loving Instagrammer has probably already seen the phenomenon of "White Ash". For example with a reference to @whiteashgang, or using the hashtag #whiteashgang.

What does White Ash mean?

The idea behind it is that weed that has been properly flushed, cured and dried will leave white ash when it burns. If there’s something wrong, it will give gray or even black ash. This test is carried out without tobacco, of course.

Dark ash would mean that there are particles in the weed that you would rather not have be there. Others say that black ash is a sign that there is still too much moisture in the flowers and that it has not been dried and cured properly.

If you use this test on a random bag weed from the black market, it will not surprise me that if none of that weed will pass this test.

Where does White Ash come from?

It actually comes from the tobacco industry. The "Cigar Association of America" has even devoted an entire article to it on their website:

The ash can tell you a lot about the quality of your cigar. It provides insight into everything from the quality of the leaves, to the workmanship of the cigar, to the type of soil it was grown in.

The way to distinguish real Cuban cigars from "fake" cigars would be to look at the ashes.

But is it bad? And is it really true that weed that does not leave white ash is inferior?

Well, as this Reddit thread also indicates, not everyone agrees. And a distinction is also made between flowers and hash:

Spliff With Dark Ash

Joint with Dark Ash

When you burn weed, or any carbon-based combustible matter, first it will turn to charcoal - black, mostly carbon, chemically changed but still able to continue burning. If you continue to burn that, you'll burn away almost all the carbon, leaving with whatever mineral content there was in the plant material - calcium, magnesium, stuff like that. This is white ash.

All cannabis becomes white ash

Then the story continues:

ALL WEED will turn into white ash if you burn it for long enough. All of it. Weed that burns to white ash very quickly, definitely does not indicate a high quality weed, if anything it indicates a low quality as there was not much much oil in the plant material to combust. Weed that stays as black charcoal for a long time also doesn't indicate low quality, it just means you're not finished burning it yet. It may have been associated with low quality, because well-dried weed will burn quicker, still-moist weed will take forever. But very sticky, high-oil weed will also stay as black charcoal for a very long time and take forever to burn into ash.


White Ash Cannabis in Pipe Bowel

White Ash Cannabis

Shitty taste

Or as the best cannabis grower in the Netherlands said when I asked him about this:

White ash does not necessarily mean good weed. Black ash does not necessarily mean a bad flush, but a bad (shitty) taste.

So what does science say about White Ash?

Dr. Allison Justice writes at the Cannabis Bussiness Times that: “The main takeaway is that white ash forms at high combustion temperatures and is mostly made up of minerals. This should lead us to question the doctrine that white ash comes from flushed cannabis plants.”

She concludes “It’s not flushing. There’s only one study done into flushing, and it’s far from complete.”

Maybe light: “It appears the manipulation of temperature and light with the goal of chlorophyll degradation and sugar transformation are major contributors to a pleasant smoke and “white” ash, not a good pre-harvest “flush.””

Should you even flush at all? Not if you’re growing organically according to Kees from BioTabs when I asked him about this. It’s also rather difficult to flush when growing outdoors too. Either way, it’s a good idea to keep growing organic.


Make of it what you will. It seems it’s possible to manipulate your plants to give white ash. And the science simply isn’t in yet. However, the cat is out of the bag and as such the term white ash seems to be here to stay. Just don’t forget next time you hear it, that you’ve learned a thing or two about it.

Text by: Mauro Picavet
The Stoned Society