Home-made CBD hash: the two production methods

Hash is a concentration of the trichomes, the resin glands visible on the surface of the flowers, which carry the bulk of the cannabinoids and terpenes. By separating those trichomes from the surrounding plant matter, you obtain a product more concentrated than the original flower. The two methods presented here rest on a simple physical principle, separation by particle size, with no chemical transformation of the molecule.

This method uses sieves of decreasing mesh, generally from 150 down to 25 microns, stacked one on top of the other. Dry, cold flowers are rubbed gently over the widest sieve: the trichomes, being smaller than the plant fragments, pass through the mesh while the leaf debris stays on the surface. Repeating the operation over finer and finer sieves refines the purity of the powder obtained, known as kief.

Chilling the flowers beforehand, in the freezer for 30 to 60 minutes, makes the trichomes easier to detach by making them more brittle. The kief collected can then be pressed, using a hand press or by simple moderate thermal compression, to form a compact hash.

This method uses very fine mesh filtration bags (generally 25 to 220 microns), ice water and crushed ice. The flowers are mixed with ice water in a bucket, stirred gently for 10 to 15 minutes to detach the trichomes under the effect of the cold, then the mixture is filtered through the stacked bags. The purest trichomes settle in the finest bag.

The residue collected, known as bubble hash, must be dried carefully before storage: residual moisture encourages mould. This method generally produces a hash with a richer terpene profile than dry sifting, because the cold better preserves the volatile compounds.

Dry sifting requires less equipment and gives a quick result, but sometimes picks up more plant debris if the flowers are not cold enough. Ice water extraction requires more steps and careful drying after filtration, in exchange for generally higher purity. Neither method uses a chemical solvent, unlike butane or ethanol extractions, which are reserved for an industrial setting.

Once pressed or filtered, hash must dry under the same conditions as any hemp extract: cool temperature, moderate humidity, away from light. Our article on drying hashish and extracts sets out these parameters. Then store the product in an airtight glass container, cool and away from light.

CBD is not a medicine. Use only flowers whose THC level complies with the French legal threshold.

Do these methods need fresh or dried flowers?

Dried flowers are suitable for both methods. For dry sifting, they must also be thoroughly cold so that the trichomes detach easily without carrying plant matter with them.

How much flower is needed to obtain a meaningful quantity of hash?

The yield varies widely depending on the variety and its richness in trichomes, generally between 5 and 15% of the initial weight of dried flowers, a ratio that remains indicative and not guaranteed.

Is the hash obtained more concentrated in CBD than the original flower?

Yes, in principle, since the trichomes concentrate the bulk of the cannabinoids. The exact concentration depends on the quality of the separation and can only be confirmed by a laboratory analysis.

Can a blender be used to speed up the separation?

That is not recommended: a blender risks shredding the plant matter and contaminating the hash with leaf fragments, which degrades the purity and the taste of the final product.