How to Extract Cannabis Resin at Home: Kief, Hash, Rosin and Beyond

The easiest and safest ways to extract cannabis resin at home are solventless: dry sifting for kief, hand-rubbing for charas, ice water for bubble hash, and heat plus pressure for rosin. Solvent methods like BHO pull more out of the plant but involve flammable chemicals and are best left to pros. Which extraction method you pick comes down to the final product you want.

How to make homemade resin with solventless extraction methods

The most common solventless ways to pull resin from buds use water or a combo of heat and pressure. They're much easier to do safely than solvent-based methods and are usually less strictly regulated.

Dry sifting

Dry sifting means physically knocking the trichomes off the flower and collecting them to make kief. A lot of weed grinders have three chambers: as you grind, the flower drops into the second chamber, which has a screen at the bottom that lets the kief fall through and collect in the third. To make bigger batches of kief, you can use silk screens to separate the kief from the plant material.

By hand

Hand-rubbing is one of the oldest ways to make homemade resin. You start with fresh cannabis (not dried or cured) and gently roll it between your palms. The sticky trichomes come off the plant and stick to your hands. Then you can scrape the resin off, or keep rubbing your hands together to form a sticky ball or stick of hash, commonly known as "charas."

Ice water or dry ice

If you want to make your own concentrates, ice water and dry ice methods are the safest and easiest. The idea is to drop the flower into ice water to freeze the trichomes, then agitate the mix to knock them loose. Next, filter everything through progressively finer screens to remove the plant matter. Set the wet resin somewhere cool and dark to dry. Then press it into hash, technically known as "bubble hash."

Heat and pressure

To make rosin, a very particular kind of cannabis resin extract, you apply heat and pressure to flower, kief or bubble hash. You can buy a purpose-built rosin press or use a hair straightener or a clothes iron. Put the flower, kief or hash between two pieces of parchment paper or in a small micron bag and squeeze it between two heated metal plates.

Heat and butter

By baking cannabis to decarb it and then simmering it in butter and water, you can make your own cannabutter. When it cools, the butter separates from the water, which you toss. The finished butter can go into all kinds of edible recipes.

Alcohol

By baking cannabis and then gently heating it in alcohol, you can also make your own tinctures, which you can take under the tongue or add to drinks.

Solvent-based cannabis resin extraction methods

In solvent extraction, a solvent is added to the plant material. Then pressure and temperature are adjusted so the solvent dissolves the compounds you want from the plant. Any leftover solvent is purged, leaving behind the oils, cannabinoids and terpenes pulled from the plant.

To get the idea, think of solvent extraction like brewing a cup of coffee. You pour hot water over ground coffee in a filter. The hot water acts as the solvent, pulling out the caffeine and the compounds that give coffee its aroma and flavor. The filter holds back all the plant matter: the coffee grounds. Hot water isn't the best solvent for cannabis, but the concept is the same.

BHO (butane hash oil): This method uses butane gas as the chemical solvent. Other hydrocarbons can be used too, like propane, hexane or dimethyl ether (DME), sold under brands like Dexso and known as DHO. There's also a method that combines BHO + DHO, called DBHO.

These methods should only be done by specialists and professionals, since they involve ingredients that can be flammable and dangerous. That's why we recommend starting out with natural extraction methods.

How to increase resin on your buds

For indoor grows:

Light is the main tool for boosting resin. Many growers swear that trichome production ramps up when plants are short on light, so a common technique is to stress the plant with total darkness for 48-72 hours, starting about 4 days before harvest. On top of that, LED panels with UV output make the plant try to protect itself by coating up in trichomes. Nutrients help too. Bloom boosters like Delta-9 (a Cannabiogen product, not the cannabinoid) are used to push flowers and trichomes. Amino acids are another good option.

For outdoor grows:

Outdoors you're working with natural sunlight, so you can't play around with the light. What does help is nutrients and stimulants to boost flowers and trichomes. Another trick some growers swear by, though the evidence behind it is thin, is putting ice on the roots every day after sundown during the week before harvest. The idea is that when temperatures drop a bit and the lights go out, resin production goes up.

Bottom line: cannabis extracts have become one of the fastest-growing sectors of the industry in recent years. They pack a high concentration of cannabinoids and open up new ways to consume, whether for recreational or medical use.

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