Rosin is a solventless cannabis concentrate made by pressing flower, kief, dry sift or bubble hash between two heated plates. The heat softens the resin and the pressure pushes it out through a fine filter bag, leaving the plant behind. Pressed from hash it is called hash rosin; from fresh frozen hash, live rosin.
How rosin is made
Rosin is made with three things: heat, pressure and a filter. The material goes into a fine mesh rosin bag, the bag is folded into parchment, and the parchment goes between two heated plates. As the plates close, the resin softens and flows out through the mesh onto the parchment while the plant stays in the bag. The Press Club’s guides put flower at about 180 to 220 °F and hash lower, at about 160 to 190 °F; Low Temp’s rule of thumb is to stay at or below 220 °F.
Kinds of rosin
Kinds of rosin are named for what was pressed, and each gives back a different share of its weight as oil:
| Kind | Pressed from | Typical return |
|---|---|---|
| Flower rosin | Dried, cured flower | 15 to 25% |
| Kief or dry sift rosin | Kief or dry sift | 30 to 40% |
| Hash rosin | Bubble hash | 60 to 70% and up |
| Live rosin | Bubble hash washed from fresh frozen plants | 60 to 70% and up |
Returns are The Press Club’s averages; clean, full melt hash presses higher still.
Rosin textures
Rosin textures change after pressing. Fresh off the press it can be glassy, sappy or saucy. Cured cold in a sealed jar it whips into a creamy badder; cured warm, the THC crystallizes out of the terpenes into jam. The texture changes, not the strength.
Why rosin counts as solventless
Rosin counts as solventless because nothing touches the resin but heat and pressure: no butane, no alcohol, nothing to purge out afterward. That is the same reason ice water hash and dry sift count, and it is why rosin grew up inside the hash world. Most rosin starts as hash, made the ways described in how to make hash; how rosin sits among the other cannabis concentrates is its own story.
Where rosin came from
Rosin came into the hash world around 2015, when growers started pressing resin out of flower with hair straighteners. As Bubbleman tells it, it wasn’t until Soilgrown Phil hit the flower with a hair straightener that rosin caught on, and Hash Church did a show on it within three weeks. He pressed his own first rosin on camera in March 2015, from a little low grade dry sift, straight after a Hash Church where Jeff Church and Soilgrown talked through their technique.
From the archive: Bubbleman on rosin’s early days
From the archive, Bubbleman on rosin’s early days in his own words, from two live Sunday shows. Tap a time to hear that moment.
Season 12, Episode 14, Skully Vibes draws live
It wasn’t until Soilgrown Phil hit the flower with the hair straightener and made that rosin. That was… I think we did a show in 2015, which would have been within three weeks of him doing it, maybe less.
On how rosin caught on
Season 12, Episode 15, The Edibles Episode, with Marigold Sweets and Space Gems
When rosin came out and we were pressing at 200 degrees Fahrenheit, literally every BHO guy was like laughing… it all tastes like burnt popcorn. I’ve still yet to taste burnt popcorn rosin. Like, my rosin tastes heavenly and wonderful and delicious.
On the early doubters
How rosin concentrate is used
Rosin concentrate is used the same ways as any other concentrate: dabbed, vaped, rolled into joints and hash holes, or cooked into edibles. Because it is solventless, many hash makers rank good hash rosin at the top of the whole concentrate world.
Rosin guides
Rosin guides, from what each kind is to how to press it:
- Live rosinPressed from fresh frozen hashExplainer
- Hash rosinRosin pressed from bubble hashExplainer
- How to make rosinTemperatures, bags and pressureHow to
- How to make hash rosinAnd live rosin, from bubble or siftHow to
- Live rosin vs live resinPressed, or solvent extractedComparison
- Hash rosin vs live rosinAnd flower rosinComparison
- Cold cure rosinCold cure vs warm cureExplainer
- PiatellaCold cured bubble hashExplainer
- SolventlessWhat the word meansExplainer
Questions about rosin
Questions about rosin, answered short:
What is rosin?
Rosin is a solventless cannabis concentrate: resin squeezed out of flower, kief or hash with heat and pressure, through a fine filter bag.
What is rosin weed?
Rosin weed means cannabis rosin, the oil pressed out of the plant or its hash. It has nothing to do with the rosin violinists rub on their bows.
Is rosin a concentrate?
Yes, rosin is a concentrate, and a solventless one: it is made with heat and pressure instead of butane, alcohol or CO2. Flower rosin, hash rosin and live rosin are all rosin concentrates, named for what was pressed.
What are rosin dabs?
Rosin dabs are small amounts of rosin vaporized on a hot surface or in an e-rig, the same way any concentrate is dabbed.
Is rosin stronger than flower?
Yes, rosin is much stronger than flower, because it is mostly the resin the plant made, without the leaf around it.
Sources for this guide to rosin
Sources for this guide to rosin:
- How to press flower rosin: a starter guide, The Press Club
- Average rosin yields from various cannabis material, The Press Club
- Rosin press temperature guide, Low Temp Industries
- How to cure rosin: cold curing vs heat curing, Low Temp Industries
- Rosin with dry sift, Bubbleman’s first rosin on camera, March 2015, Bubbleman’s World on YouTube
- Hash Church Season 12, Episodes 14 and 15: Bubbleman on rosin’s early days, linked above