A whole bud is a sealed thing. Its resin sits folded into the bracts and sugar leaves, and most of its aroma stays there until somebody opens it up. Grinding is that somebody. It is the last thing that happens to the flower before fire or heat, and for all the patience a grower spends on the dry and the cure, it is usually done in about four seconds by a person who is talking to someone else.

We think it deserves a minute.

The guides that rank for this question agree with one another closely. They explain that grinding helps flower burn evenly, list the grinders by how many pieces they come in, recommend a size for joints and another for vaporizers, and finish with a tour of kitchen substitutes (the pizza cutter turns up more often than you would guess). We will go through that quickly. What none of them discuss is when to grind, which in our experience changes the taste of a joint more than any tool does.

Why flower gets broken up at all

A dense bud in a paper burns unevenly. The outside chars while the center sits there, and the joint runs down one side. Broken flower packs into an even column that lets air through at the same rate from end to end, and in a vaporizer it exposes far more surface to the heat, so the chamber gives up its aroma in one session instead of leaving half of it inside a nugget.

The cost is the same in every method. As our guide to cannabis trichomes explains, a mature resin head is a drop of oil balanced on a stem a fraction of a hair’s width across, and it breaks off about as easily as that sounds. Every way of breaking up flower knocks some of those heads loose. The useful question is how many, and where they end up.

By hand

Hold the bud by its stem and pull it apart along the natural seams, the way you would separate a head of broccoli into florets, then pinch those pieces smaller over a clean card or a small dish. Gently. Rolling flower hard between finger and thumb crushes it to a paste.

Your fingers are warm and slightly greasy, and the dark tacky film left on them afterward is resin that will never reach the paper. Dry hands help. So does working fast and handling each piece once.

With scissors

This is our preferred method, and it is the one most guides file under emergencies. Small, sharp scissors (a pair of good nail scissors does the job, so do the curved ones sold for trimming) cut through a bud cleanly instead of tearing it, which leaves more of the resin on the flower and less on you. Snip over a clean card or into a shot glass, keep the blades pointed down, and stop when the pieces are the size you want. Wipe the blades with a little alcohol afterward or they will gum shut by Thursday.

In a grinder

A grinder is fast and consistent, and nothing prepares flower for a table of six more easily. We own one. Load it with pieces about the size of a fingertip, packed around the outside of the teeth rather than piled in the center, and give it a few short turns instead of twenty long ones. Open it and look before you decide it needs more. Over-grinding is the most common mistake we see, and a grinder with dull teeth makes it worse, mashing the flower where a sharp one would cut it.

Then there is the kief catcher, that third chamber with a fine screen above it. The golden powder collecting in it is your flower’s best resin, sifted out of every session a little at a time, and saving it for a special occasion means smoking slightly lesser flower for months to get there. If your grinder has a screen, tip the kief back over the flower you are about to use. Or buy a two-piece and skip the question entirely.

Kitchen substitutes have their uses, though a blade coffee grinder turns good flower to dust in about a second and leaves it tasting of last week’s espresso. Keep it for coffee.

How fine

For a joint, aim for even pieces somewhere between a lentil and a grain of rice, with no powder and no stems. Powder packs too tight and draws hard. Large chunks leave air pockets, and our guide on how to choose rolling papers covers what a loose pack does to the burn. A pipe can take something coarser. In a dry herb vaporizer, conduction devices like a medium-fine grind packed snugly against the walls, while convection devices prefer a coarser, looser fill that lets the air find its way through.

Moisture changes all of this. Flower cured to the water activity craft growers aim for, roughly 0.55 to 0.62, breaks into clean pieces with a little spring left in them. Flower that has dried out shatters to dust at the first touch, and damp flower clumps and gums the teeth. Grinding cannot fix either. Our guide on how to store cannabis flower can, for the next jar.

Never grind straight from the refrigerator. Cold makes trichomes brittle, which is exactly what hash makers want and exactly what you do not.

When to grind

Grind last, once the paper is out and everyone has found a chair. The moment flower is broken, every resin head that was folded safely inside the bud is open to the air, and the lightest aromatics leave first: the bright citrus and pine notes that make a cultivar recognizable. In the skunky cultivars it is worse. The sulfur compounds behind that smell are among the most fleeting in the plant, and ground flower left in a grinder overnight loses its skunk before it loses anything else.

People grind ahead because it is tidy, and because a full grinder makes a handy little tin to carry out the door. We would still talk you out of it. Ground flower is the most exposed form cannabis takes, which is why our guide on how to judge a pre-roll spends so long on the grind, and an evening’s head start on that exposure is an evening’s worth of aroma you will not get back.

You can taste the difference without taking our word for it. Take one bud and split it. Break up half in the afternoon and leave it in an open grinder. At night, snip the other half with scissors and smell the two piles side by side before you roll anything. The fresh pile is louder. Often it is also more specific, the difference between “citrus” and the particular sharpness of grapefruit pith, which is the whole reason anyone keeps tasting notes at all.

A note on stems

Pick them out, every one, because a stem in a joint pokes through the paper and a stem in a vaporizer just sits there tasting of wood.

Our position

We roll pre-rolls ourselves, the Parlor Smokes in The Parlor, so we have thought harder than most about what happens to flower between the jar and the paper.

Use scissors when there is time and a sharp grinder when there are guests. Grind to a rice-sized, even fill for a joint and a little coarser for anything else. Skip the kief catcher, or empty it back into the flower every time. And grind last, minutes before the flame rather than hours, because the cure took weeks and the aroma it built can be gone by the end of an afternoon in an open tin.

How to Grind Cannabis