Fermenting crocks have been around for centuries, used by our ancestors to ferment produce in a controlled environment. They come in a few different shapes and sizes, but they all have the same purpose.
Although there are specially designed mason jars for fermentation nowadays, a classic fermenting crock can ferment a larger batch. They also last forever and look great on your kitchen counter.
Learning how to use a fermenting crock is easy, and doesn’t take much to get started. Here’s everything you need to know to start experimenting with your own fermenting crock today.
Estimated reading time: 6 minutes

History of Fermenting Crocks
Traditionally, fermenting crocks are stoneware jars used to hold and ferment a large number of vegetables. Researchers have found evidence of jars being used for fermentation hundreds of years ago in the European and Asian continents.
By fermenting their excess produce from the fall harvest, people could safely store food throughout the winter. Since refrigeration is a relatively new invention, fermenting food was one of the most common ways to preserve food for centuries.
The most common fermented food made in the crocks is sauerkraut. In many countries today, people still make sauerkraut in a traditional fermenting crock.
The crocks’ popularity continues today because they’re easy to use, don’t have any fancy parts, and don’t need electricity. Plus, the beautiful stoneware looks like part of your kitchen decor.
In fact, when they’re not fermenting, many people use these crocks to hold kitchen utensils or other items on the counter. Your fermenting crock could easily become one of your essential homestead kitchen items.
Today, as more people become interested in learning how to homestead, make pickled vegetables, and secure their food supply, fermenting crocks are gaining attention.
The Two Types of Fermenting Crocks
If you’re interested in getting started with a fermentation crock, keep in mind there are a variety of sizes, and two different types of fermenting crocks: water-sealed crocks and open crocks.
Water-sealed crocks have a large stoneware jar, used as the vessel, and a stone lid to place on top. Between the lid and the vessel, there is a lip that you fill with water. This creates an airtight seal between the lid and the jar, keeping oxygen out of the crock.
Keeping oxygen out of the fermentation process is key since oxygen can create mold in your preserved food. On the other hand, you need to let gas escape from the fermentation vessel as it builds, otherwise, the vessel can explode.
Luckily, the ingenious design of these water-sealed crocks allows them to “burp” to exhaust the necessary gas. This means gas will push through the water and escape the vessel without letting any oxygen in.
Open crocks have the same general design as a water-sealed one, but they don’t have a lid or a lip for water sealing. Essentially, it’s a large stone jar with no top.
Open crocks come in a variety of sizes, including two, three, and five-gallon volumes. They’re easy to clean and less expensive than water-sealing crocks.
Open crocks operate by using fermenting weights to keep your produce fully submerged in the brine, so no oxygen can get to the food. You can buy these weights, or use something heavy and food safe from around the house like a small cast-iron skillet.
Whatever you choose, make sure it’s completely clean of any bacteria so mold doesn’t form in the fermentation. I usually boil my weights beforehand just to be absolutely sure.
How to Use a Fermenting Crock
Using a fermenting crock is an easy way to get started canning right now. (Tip: learn safe canning and safe preservation methods right from the start. We suggest the Ball/Bernardin Book of Canning for beginners.)
The best thing about crocks is how easy they are to use. For either type of crock, make sure you clean it and wash your vegetables before getting started.
Depending on what you’re fermenting, you may want to chop or slice your vegetables, although you can ferment them whole as well.
Your exact brine solution will vary depending on the type and amount of vegetables you plan to use. Get yourself a fermentation recipe book, pick an easy one to start, and follow the measurements.
Once you have your brine and vegetables in the crock, place the weights on top of the produce. Make sure the vegetables are completely submerged.
If you use a water-sealed crock, add the water to the lip and then place the lid on top. The water keeping the seal will evaporate, so check on it every day to see if more water needs to be added.
With an open crock, you can simply put a dish towel over the top. You should check on your crock every day to monitor for any mold, moisture, or weight-shifting issues.
After a week or two, your food will be fermented and ready to enjoy. Depending on how tangy you like your fermented food, you can leave it in longer.
Do some taste tests after 12 - 14 days and decide if you want to let it go for longer. Everybody has different personal preferences!
Why Use Fermenting Crocks?
Using fermenting crocks to make tasty and preserved food benefits you in a few different ways. When food ferments, it kills off the bad bacteria and keeps the good ones.
These good bacteria have a plethora of benefits for your gut biome and digestive tract, as well as overall health benefits.
Fermenting crocks also give you the ability to ferment a large amount of produce all at once, rather than multiple little batches in smaller mason jars.
For example, if you’re making a big batch of sauerkraut, it’s easiest and most efficient to use a fermenting crock. Also, the simple design of fermenting crocks makes them very easy to clean and maintain.
What to Watch Out For
If you’ve inherited or purchased a used fermenting crock, make sure you check for any cracks or issues with the jar. Although they’re made from sturdy, thick, stoneware, some of the jars may have cracks along the top rim that will allow oxygen into the vessel or leak fluid.
Also, while the fermentation process is active, monitor it daily for issues such as mold or anything else that seems out of place.
If you’ve never used a fermenting crock before, don’t worry. It’s one of the most simple tools to use in a kitchen and takes minimal effort to achieve a successful fermentation.
If you have an abundance of fall vegetables and want to try something different with them, invest in one of these handy crocks.
The open crocks are relatively cheap and will last for the rest of your life. Try out a few different fermentations, and let us know what your favorite one is!
Learn more about fermenting crocks in this piece from The Prairie Homestead and this guide from Stone Creek Trading.
Interested in learning more about food preservation off the grid? Continue reading below...
This post is part of the Homestead Blog Hop #312!
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Michelle @ Moms Are Frugal
This was very interesting, and I learned something new. I have never heard of a fermenting crock, but your post was very helpful.
Linda Carlson
Great information. I have often thought about using a crock but have always used jars. Now I am motivated to try it.
Sissy
We must be on the same wavelength! I was just telling my husband yesterday that I needed a larger crock. Great information!
Ann @ Live The Old Way
This is fascinating and full of great detail! I had no idea there was more than one kind of crock. Thank you for sharing this with us at the Homestead Blog Hop!
Michele
Really interesting! I make kimchi and always follow my Thai MIL's recipe, which includes "leave it out for 3 days and if it doesn't explode, you did it right". Very comforting. I would love to try making it in the water crock. Less explosive lol
Deborah Davis
Hi Sarita, Happy Earth Day! I hopped by from Homestead Blog Hop to read your wonderful post about fermenting crocks. I love to make gut-healthy, fermented food, especially sauerkraut and kimchi, so this article was quite interesting to me. I look forward to getting my first fermenting crock. I am delighted to visit your blog and I shared your post on social media. I also joined your email list. All the best, Deborah