How to clean a matcha bowl (chawan)

Search for this and you will be told how to wash a whisk. Nearly every result is about the chasen — the videos, the forum threads, the shop guides. The bowl, which is the easier of the two objects and the one you actually drink from, is left to a sentence at the end.

Here is the whole of it. Warm water and a soft sponge, and unlike the whisk, a little mild soap is fine — the inside of a bowl is glaze, and the whisk is porous bamboo. The part that needs real attention is the one nobody mentions: the unglazed ring of raw clay on the underside. It holds water, and if you put the bowl away before that ring has dried, that is where trouble begins. And most staining is prevented before you whisk, not scrubbed off afterward.

The bowl is not the whisk, and the rules are opposite

Both objects arrive in the same box, so one set of instructions gets applied to both. It should not be.

Cleaning the whisk is the harder problem and has its own article. What follows is only the bowl.

The step that prevents stains, which happens before you whisk

Run warm water into the bowl and let it stand for a few minutes before you make tea, then pour it out and wipe it. Five minutes is enough.

Two things happen. The clay takes up water, so there is less room for matcha to work its way into the surface and into any fine crazing in the glaze. And the bowl comes up to temperature, which matters more than people expect — a cold bowl pulls the heat out of a small volume of tea immediately, and the temperature you whisk at is one of the few things that reliably changes how the tea tastes.

Both of the guides that actually address the bowl tell you how to remove stains. Neither tells you how to avoid them. This is the step, and it costs nothing.

The everyday wash

The unglazed foot, which is the actual answer

Turn a Japanese tea bowl over. Tea that dries on it leaves a mark for good, which is the one place matcha really does stain. The ring it stands on — the kodai — is almost always left bare, a band of raw clay with no glaze on it. On mine it is pale cream under the black. It is left that way deliberately, so you can see what the bowl is made of and how it was cut.

That bare ring is the only absorbent part of the bowl, and it is the part everyone dries last and looks at never.

Wipe the inside and the bowl looks finished. But the foot has taken up water, and if you set it down flat on a shelf, the ring sits in its own dampness with no air moving through it. In a cupboard, over days, that is how a bowl picks up a musty smell or a bloom of mold on the clay.

So dry it the way Japanese potters describe: stand the bowl at an angle, or upside down and propped, so air reaches the foot from underneath. Leave it out until the ring is dry to the touch. It is the same test as the whisk, for the same reason — what matters is whether air can move, not how thoroughly you wiped.

Okakura Kakuzo, writing about the tea room in 1906, put the standard higher than any of this: "Not a particle of dust will be found in the darkest corner, for if any exists the host is not a tea-master." The darkest corner of a tea bowl is the inside of its foot.

Stains, and whether they are a problem

On a dark interior, you will mostly not see them. This is part of why so many bowls for thin tea are black or iron inside — the green reads beautifully against it, and so does nothing else. On a white or pale interior, matcha shows as a green-gray film within a few weeks of daily use.

Vinegar comes up often. A weak solution occasionally is harmless on a glazed interior, rinsed well. I would not use it on unglazed clay, and I would not make a habit of it, because the thing it is being asked to fix is usually the thing five minutes of soaking before use would have prevented.

The dishwasher, and the new bowl

Most tea bowls are not made for the dishwasher. Three reasons, in order of how likely they are to actually cost you the bowl: it knocks against other things and chips at the rim; the cycle takes it from hot to cold quickly, which is what cracks glaze; and dishwasher detergent is mildly abrasive and will dull a matte surface over a year. A bowl takes thirty seconds to rinse by hand.

A new bowl usually needs nothing. You will find instructions for medome — simmering the piece gently in the cloudy water left from rinsing rice, for about fifteen minutes, or soaking it half a day. This is a real practice and it works, but it is for unglazed earthenware and for pieces with open crazing, where the starch seals the surface. A standard glazed tea bowl does not need it, and I have never done it to mine. If your bowl is raw clay inside, or the crackle is visibly open, it is worth doing once.

Where I land

Rinse it warm while it is still warm, dry the inside, and leave it tilted overnight so the foot can breathe. That is the whole method, and it takes less attention than the whisk does. If you only change one habit, make it the five minutes of water before you whisk — it removes most of the reason people go looking for this article in the first place.

The bowl I use every morning is matte black Mino-yaki with an unglazed cream foot, and after months of daily tea the inside looks the same as the day it arrived. Not because I am careful with it. Because the interior is dark and it gets wet before the tea goes in.

Questions I get asked

Can matcha bowls go in the dishwasher?

Most are not made for it. Chipping at the rim is the likeliest damage, thermal shock is the worst, and detergent slowly dulls a matte glaze. Hand rinsing takes half a minute and there is nothing to gain by automating it.

Are matcha stains hard to get out?

Not if you rinse while the bowl is still warm. Left to dry and repeated daily, a film builds that needs a soak and a soft sponge, and occasionally a baking soda paste. Stains held in the crazing of an older bowl are not worth removing — that is the bowl aging.

Should I use soap on a matcha bowl?

Mild dish soap on the glazed inside is fine, and this is where the whisk rule misleads people. The chasen must never meet soap because bamboo is porous and holds it. A glazed bowl is not porous. Keep soap off the unglazed foot and rinse well.

Do you drink directly from a matcha bowl?

Yes — that is what a chawan is for, which is also why a heavily pulled pouring lip is a mixed blessing on one. Whether you want a spout comes down to whether you drink from the bowl or pour out of it.

Do I need to season a new bowl before using it?

Almost certainly not. Sealing with rice water is for unglazed earthenware and pieces with open crackle. A glazed bowl for thin tea can be rinsed and used the same day.

Where this fits

Care is half of the reason a bowl lasts; the other half is choosing one that suits how you drink. How to choose a matcha bowl covers width, depth and shape, the cloth it is wiped with is worth knowing before you reach for a tea towel, and cleaning the whisk is the harder companion to this one. If you are assembling the pieces, the beginner's guide covers the scoop and the sifter as well, and the complete set puts the bowl, the whisk and the tea together.

Written by Mio.K, who chooses everything in this shop by hand in Japan.