How Long to Soak Terracotta Pots (and When Not to Soak at All)
Short answer: How long to soak terracotta pots depends on the pot, not on one rule for all clay. A Römertopf-style roaster gets about 15 minutes in water before every use. A tagine gets a long soak once, when you season it. A Donabe is seasoned with rice porridge instead of being soaked, and unglazed stoneware like a pizza stone should not be soaked at all.
Follow the maker’s instructions when you have them. If you remember one thing, make it this: soak only when the maker says to, and heat any clay pot slowly either way.
This guide is about cooking pots, not garden planters. Every instruction below links to the page it came from, and we last checked those pages on 1 November 2026.
Why the advice online contradicts itself
Clay pots differ in how much water they take in. Ceramics reference site Digitalfire says most stonewares have less than 2 percent porosity, while earthenwares fired to cone 04 have about 10 to 12 percent. It measures porosity as the weight a piece gains after boiling in water. Firing changes the number. The same page lists one terra cotta body fired hotter at only 6 percent. So treat these as test figures, not as a number for your pot.
That gap explains most of the confusion. A low-fired terracotta roaster can hold a lot of water, which is the whole idea behind steam roasting. A stoneware piece holds very little, so soaking it adds almost nothing. Our guide to unglazed clay and stoneware cookware covers how firing sets that difference.
Makers add to the confusion because their clays differ. Miriam’s Earthen Cookware uses primary clay and says not to soak its pots before seasoning, because soaking can waterlog the pot and may crack it. That comes from its seasoning instructions as relayed by clay-cookware teacher Sally Zim. The same page says pots made from secondary and tertiary clays are soaked overnight.
How long to soak terracotta pots, pot by pot
Here is what each set of instructions says about how long to soak terracotta pots.
| Pot | First use | Before every use | Source |
|---|---|---|---|
| Römertopf-style clay roaster | A “really good soak,” then brush off clay dust | Moisten it: about 15 minutes in a basin, or 30 seconds with the lid under warm water if you’re rushed | Römertopf care sheet |
| Tagine | Soak at least 2 hours (overnight is best), dry, then season with olive oil in the oven | No soak | Moroccanzest |
| Terracotta casserole (Forno Bravo guide) | Soak a couple of hours for pots up to 16 cm wide, about four hours for larger, thicker ones | No soak. Soak once, not before every use | Forno Bravo |
| Iga donabe | Season with rice porridge, not a plain soak | No soak listed | Nagatani Seito FAQ |
| Unglazed stoneware baking stone | No soak | No soak | Lehman’s, Yoder |
Instructions differ even inside one brand. A retailer’s listing for Römertopf’s round bread oven says to soak the lid for 45 minutes before first use, and to soak only the lid, for 15 minutes, when baking bread. The Römertopf sheet above is a distributor’s copy with no date, so read the one in your box.
Do you need to soak a clay pot every time?
Only if the maker built the cooking method around it. Römertopf did. Its care sheet says the pores store the water, so you moisten the pot before every use and start it in a cold oven. After about 100 uses, it says to boil the pot in clean water for 30 minutes to reopen the pores.
America’s Test Kitchen describes the same roaster method as a 15-minute soak and a cold oven. Its test compared a clay roaster with a Dutch oven on one chicken recipe and found both equally moist. It did not test soaked clay against dry clay, so it says nothing about what the soak adds.
Not every terracotta pot follows that rule. Oven maker Forno Bravo says to soak terracotta cookware once, “not before every time it is used”. It says “the longer the better,” and gives about four hours for larger, thicker casseroles. That is the opposite of Römertopf’s every-use soak, which is why the maker’s sheet matters more than any general rule.
A tagine works differently. Moroccanzest, a tagine-focused cooking site, puts the soak in the one-time seasoning. Its author says re-oiling every 10 to 15 uses is optional and needs no soak or oven time.
A donabe goes the other way. Seller Toiro Kitchen says seasoning with rice porridge helps the starch fill tiny gaps in the clay. Nagatani Seito, which makes Iga donabe, says in its FAQ to season again if the pot sits unused for more than two to three months. It also says the donabe skillet and ceramic grillware need no seasoning at all.
Why a wet pot can crack
Steam is the risk. Digitalfire describes the kiln version: heating unfired clay too fast through roughly 80 to 250°C (176 to 482°F) is the most common cause of cracking or even explosive failure, because water vapor can’t escape fast enough through the pore network. That describes unfired clay in a kiln, not a finished pot in your oven. Treat it as the mechanism, not a cookware test.
The care advice for finished pots points the same way. Römertopf says to start in a cold oven, never add cold liquid, and rest a hot pot on a folded towel. Food blog Just One Cookbook says to make sure a donabe’s bottom is dry before you cook and calls the pot fragile with quick temperature changes.
Pots you should not soak
Unglazed stoneware is the clearest case. Lehman’s sells an unglazed, Ohio-made pizza stone it calls vitrified and non-absorbent. Its care notes say not to soak it before use. Yoder’s care sheet for a porous baking stone says not to wash or submerge it and not to expose it to thermal shock. The two describe their stones differently and give the same instruction.
Glazed stoneware follows a similar rule. Weber’s glazed baking stone can be hand washed with mild detergent, but its care notes still say not to soak or immerse it.
If you have no instructions
Skip the soak and heat the pot slowly. That is a judgment call, not a tested result. None of the sources here tested soaked pots against dry ones for cracking.
The reasoning is simple. One donabe guide says to start with a dry bottom, and one maker warns that soaking can waterlog its pot. The likely cost of skipping the soak is less steam in a pot built around it. That is easy to fix once you track down the maker’s sheet. Search the brand and model with “care instructions,” or ask the seller.
The verdict on how long to soak terracotta pots
How long to soak terracotta pots comes down to the maker. Soak a Römertopf-style roaster for about 15 minutes before each use, if its maker says so. Some terracotta casseroles are soaked just once, for a few hours. Soak a tagine once, for at least two hours, when you season it. Season a donabe with rice porridge instead of soaking it. Leave unglazed stoneware dry.
If you can’t tell what you have, skip the soak and heat the pot slowly. Any number you find online is probably right for the pot it was written about. Check that it matches yours.
