What is bubble hash?
Bubble hash is the resin of the cannabis plant, separated with ice-cold water. The resin sits in tiny glands called trichomes, mostly on the flowers and the small leaves around them, and that is where nearly all the THC and terpenes are made. Researchers at the University of British Columbia found the stalked glands, the big mushroom-shaped ones, carry the most.
Bubble hash is that resin with most of the plant taken away. Other names for it: ice water hash, water hash, ice hash. Nothing touches the resin but water, ice and mesh, so it's solventless.
It isn't kief. Kief is the loose powder sifted off dry buds, and along with the resin heads it carries stalks, bits of leaf, pollen and dust. Bubble hash comes from the same glands, washed off in water, which leaves less of that plant dust behind. Our guide to the other types of hash covers dry sift, charas and the pressed slabs.
How is bubble hash made?
The whole method rests on one trick: in ice water, the resin turns brittle while the rest of the plant stays bendy. Stir the two together and the resin heads snap off.
- Chill. Buds or trim go into a tub of ice and cold water. Fresh-frozen plants are common because frozen resin breaks off cleanly.
- Stir. The mix is stirred gently, so the brittle heads break loose without shredding the leaf.
- Filter. The water runs through a stack of mesh bags, each finer than the last. The top bags hold back plant matter, and the cleanest, ripest heads collect in the middle sizes, the 73 to 120 micron range rosin makers prize.
- Dry. The wet hash is spread out and dried, often freeze-dried. Water left in it lets mould grow, so this step matters.
- Press or keep loose. Some bubble hash is sold as loose, sandy crumbs. Ours is pressed into bars in BC.
The water takes a small share of the lighter terpenes with it, which is one reason the best washes start from very fragrant plants.
Why is it called bubble hash?
Good bubble hash bubbles when it meets heat. The resin melts and boils, while leftover plant matter just chars, so the cleaner the hash, the more it bubbles. That is the explanation most sources give, and it doubles as the oldest quality test going: heat a crumb and watch.
Two other stories get told. The mesh bags used for the wash went on sale in the late 1990s under a "bubble" name, and they helped spread the word. Some say the name is about the foam that sits on top of the wash water. Nobody has settled who said it first.
Our Watermelon Zkittlez Bubble Hash page puts it simply: good ice water hash bubbles over a flame, and that is where the name comes from.
What do the bubble hash stars mean?
Bubble hash is graded on a six-star scale, and the stars answer one question: how cleanly does it melt? It's a grower's convention judged by eye and by heat, not a lab number.
| Stars | How it melts | Best for |
|---|---|---|
| 1 to 2 | Carries plant matter, leaves residue | Cooking, topping a bowl |
| 3 to 4 | Half melt: bubbles, leaves some traces | Joints, bowls, pressing |
| 5 | Nearly melts away, a faint ring left | Dabbing, top rosin |
| 6 | Melts almost completely | Dabbing |
Five- and six-star hash is the dab grade and is usually what gets sold as full melt; six-star is the top. So all full melt is bubble hash, but most bubble hash isn't full melt.
Our bars aren't sold by star number. They sit a grade above our AAA pressed hash and are made for joints and bowls.
Bubble hash vs kief, pressed hash and rosin
- Kief: resin sifted off dry flower. It comes from the same glands but carries more plant dust.
- Pressed hash: most traditional slabs are dry-sifted resin pressed with heat. Bubble hash can be pressed too, as ours is. The difference is how the resin came off the plant: through dry screens or through ice water.
- Rosin: press bubble hash with heat and the resin oozes out as a sticky oil. That is hash rosin, the step-up for a dab rig, and it fills our Live Hash Rosin jars.
How strong is bubble hash?
Strong, by flower standards. A peer-reviewed review puts water hash at about the same strength as dry-sifted kief, roughly 35 to 50% THC, and reported numbers for bubble hash run from about 30 to 60%. Where a batch lands depends on the starting flower and the grade.
Ours is labelled 45% THC, about one and a half times our flower, which is mostly labelled 27 to 30%. Start with a crumb the size of a grain of rice and give it 15 to 30 minutes before adding more.
How it feels follows the strain it came from. Hash from an indica like Death Bubba leans sleepy; hash from a sativa like Maui Mango leans upbeat.
What colour should bubble hash be?
Anywhere from light blonde to dark brown. Resin glands start clear, turn milky and then darken as the plant ripens, so the harvest timing shows up in the colour. Plant matter pushes it greener and darker, and pressing, age and air darken it further.
Colour isn't a grade on its own. Our seven bars show it: Purple Punch Bubble Hash presses into a light tan bar, because purple flowers don't make purple hash, while Tropicana Kush comes out a glossy caramel-brown. Same wash, same grade.
Smell is the better guide. Good bubble hash smells like the strain, only louder: our Maui Mango smells like ripe mango, while Death Bubba is all skunk and pine.
How do you smoke bubble hash?
Mixed with flower, the same way as other hash:
- Joint: crumble a pinch along the middle of the flower before you roll, so it melts in instead of dripping out.
- Bowl: pack the flower first and scatter the crumbs on top.
- Dry herb vape: a few crumbs between thin layers of flower.
Can you dab it? Only the cleanest. Five- and six-star hash melts on a hot banger; lower grades char and leave a black film. Our bars are for joints and bowls, and for a rig we press the same kind of resin into rosin. Our guide to smoking hash walks through six ways in more detail.
Keep it sealed, cool and dark.
All seven of our bubble hash strains sit with our pressed slabs and temple balls in Hashish.