Rosin is a popular cannabis concentrate that is known for it’s potency and flavor—without the use of chemicals. Because of the way it’s made, rosin carries over a lot of aroma and flavor from the original plant used to make it. Just like essential oils, rosin is solventless, meaning it’s not made with ethanol or alcohol. Instead weed material is pressed between two heated plates, squeezing out a gooey oil- or honey-like extraction.

The low heat used to press rosin means terpenes are better preserved, making rosin more terpy and flavorful. Because rosin is made by hand it is usually more expensive, but it is also considered to be “cleaner” without the chemicals. 

Rosin is often sold in globs in individual packages meant to be dabbed in a dab rig, but more and more, companies are putting rosin in cartridges for easy, discreet consumption through a vape pen or 510 thread rechargeable battery. 

Check out our video on how Nevada producer CAMP makes rosin carts, above.

Types of weed used for pressing rosin

Rosin can be made from flower, kief, or hash. The quality of the starting material will determine the quality of the finished, pressed rosin—fire in, fire out, as they say. 

Trim or shake will produce low-quality rosin that will be low in potency and flavor, as trim and shake don’t have much THC and are harsher when smoked than buds. The same is true for low-grade kief or hash. 

When flower is used for pressing rosin, it is often dried, but the above video from CAMP uses fresh frozen flower to produce ice water hash—this makes their product live rosin, since frozen plants are used instead of dried. Buds are flash frozen in their prime, before terpenes have time to degrade, making the final product incredibly terpy and flavorful.

There are a lot of consumer rosin presses out there to make your own rosin at home, fresh and on-demand. But rosin carts typically need to be bought from licensed dispensaries because of the process of adding rosin into a cartridge. There are refillable vape carts out there, but most vapers find it easier (and less messy) to buy a pre-filled cart. 

Cannabis company CAMP uses fresh frozen plants as source material for their live rosin carts, and turn it into ice water hash, but rosin can also be made with dried cannabis, kief, or hash. Texture and consistency of the finished product may vary depending on the source material, and thick rosin may be difficult to put into a cart and properly vaporize.

CAMP grows all of their own weed plants, as opposed to sourcing starting material from another farm. Plants are grown to maturity and harvested. Buds are then put in a cryogenic freezer, keeping below -42°F/°C, which helps preserve cannabinoids and terpenes. 

Once frozen, buds are placed in giant buckets to make ice water hash. Ice water is added to the buckets and then buds are stirred, freezing trichomes and breaking them off. The water/trichome mixture is drained and the ice water hash separated through a series of sieves with finer and finer meshes. The hash is then dried in an oven. 

Once dry, the hash is then pressed into rosin, poured into vape carts, and ready for the dispensary. The rosin is not diluted and there are no additives introduced when added to the vape carts. This fresh frozen, ice water hash method ensures that a high level of terpenes and cannabinoids are kept in the final rosin, giving the consumer a terpy, flavorful experience. 

Pat Goggins

Pat Goggins is a senior editor who handles Leafly’s informational content and specializes in cannabis cultivation after working for a commercial grower in Oregon. When not fixing typos, you’ll probably find him on a boat or in the mountains.

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