Photos by Lauren V. Allen

There are probably more sourdough starters quietly bubbling away across America than ever before. But if you’re new to the home bread-baking game, let us help you catch up.

“Sourdough” bread is leavened with natural bacteria and yeast found in flour (and its surrounding environment), as opposed to loaves that rely on commercial yeast. Sourdough’s signature flavor comes from various species of lactic acid–producing bacteria, that same bacteria that gives sour cream, yogurt, and buttermilk their tang.

All sourdough breads (and myriad sourdough-based baked goods) begin with a live culture, called a “starter” (aka levain or “mother”) that is added to the dough to make it rise. Although you can make excellent bread (such as our No.8 No-Knead Bread) sans starter, sourdough bread has a few advantages: it has a more complex flavor, the nutrients and starches in sourdough are easier for your body to absorb, sourdough bread stays fresher, longer, and sourdough contains less gluten than commercial bread, making it more tolerable for gluten-insensitive digestive systems.

Making a starter couldn’t be more simple—mix flour and water, wait, repeat—but the Internet might have you think otherwise. If you’re sourdough curious, you’ve probably seen loads of tutorials that offer more complicated pathways to a starter, from adding pineapple juice, raisins, and potatoes, to following a strict feeding schedule that engenders postpartum stress.

The easiest way to make a starter is to not make one at all. Chances are you know a friend or local bakery who’ll gift you a spoonful of theirs, and all you have to do is feed it water and flour on a semi-regular basis. There’s also a cottage industry of mail-order starters, but you’d really just be wasting your money: Despite the lore, a starter that can be traced back to an 1800s homestead won’t make discernibly better bread than a starter made in a 2020 apartment.

Our starter-making method is as basic as it gets, and lets nature and time do most of the work. Let’s get...started:

Preparing the starter

The most important step in making a starter is to accept the fact that it might fail. This happens all of the time, and can be caused by many factors, but you’re only investing a few minutes of effort and a few pennies’ worth of ingredients in your starter, so don’t make an emotional investment as well. If your starter doesn’t take (we’ll explain how to spot this below), just try again. We’ve made dozens of starters, and never had more than one successive failure.

Once you’re mentally ready, grab a 1-quart glass jar or plastic storage container and wash it well (even better: sanitize it in the dishwasher or with boiling water). Flip-top jars and plastic deli containers are great, because you can leave the top cracked open to allow for some airflow (which your starter will need).

Add 150g (about 1¼ cups) of flour and 150g (about ⅔ cup) of warm (~90°F) water to the jar, and stir with a clean spoon until you don’t see any dry flour. Use the type of flour you plan to bake with most of the time: all-purpose, whole-wheat, and bread flour—or some combination thereof—will all work. If you’re not sure what flour you’ll use down the road, use all-purpose. (Click here to learn more about the best flours for bread baking). For the water, go ahead and use your tap; if it works, you won’t have to worry about using filtered or bottled water later on. If you know your water is chlorinated, though, it’s best to use filtered or purified water. Do NOT use distilled water, which lacks the minerals that bacteria need to thrive.

Let the starter sit, uncovered, for a few minutes, then cover the jar with a clean kitchen towel and secure it with a rubber band. Let the starter sit on the counter until the next day. The ideal temperature for a new starter is around 70°F; if your kitchen is colder than this, place the starter on top of the refrigerator or another warm spot.

Feeding the starter

Remove the towel and take a look at your starter. If you see some small bubbles, great! Yeast is present and beginning to do its job. If you don’t, cover the jar again and wait another day. If you still don’t see any bubbles after 48 hours, empty the jar and start over. (What went wrong? Your kitchen might be too cold, so let the next starter rest in a slightly warmer spot. Or there might not have been enough natural yeast present, so try a different flour).

Once your starter shows signs of life (i.e. bubbles), you’re ready to feed it. Spoon out and discard most of the starter, leaving about ¼ of it behind in the jar (just eyeball it). Add 100g (¾ cup) flour and 100g (½ cup) warm water and stir to combine. Cover the jar again with the towel and let it rest. A time lapse of your starter would show it rising and bubbling over the course of the day, then sinking once the yeast run out of food. This is when it’s ready to be fed again.

Repeat this process every day—dumping out most of the starter, and adding 100g each of flour and water—for a week. As time goes on, you’ll notice a more pronounced aroma: a little funky, a little musty, like fermenting grapes. This is your starter becoming more complex, and these flavors will eventually be passed on to your bread. You might also notice some dark liquid floating on top of your starter; this is the alcohol produced as yeast ferments, aka “hooch,” and it will smell boozy. This is normal, and simply a sign that your starter is ready to be fed again after you pour out the hooch.

Maintaining and using the starter

After a week, your starter is fully matured and ready to use to make bread or any other sourdough recipe. A few hours before you’re planning to use your starter, feed it; once it’s about doubled in size, it’s ready to be used. (We place a rubber band around our starter’s container, and line it up to the top of the starter after it’s been fed; this way, it’s easy to track its growth). You can also make sure the starter is fully ready by doing a float test: Add a spoonful of starter to a glass of cold water; if it floats on the surface of the water, it’s ready to use. If it sinks, feed it and wait another day.

How you maintain your starter from here on depends on how frequently you use it. If you’re a power baker and plan to use it several times a week, leave it on the counter and feed it daily, discarding about half of the starter before you add equal weights of water and flour. If you’re planning to use your starter about once a week, leave it in the refrigerator and feed it the day before you’ll be using it. Wherever you store your starter, you should keep it covered, but allow for a little airflow. With a flip-top glass jar, close the jar but leave it unlatched. With a plastic deli container, poke a couple of holes in the top or leave it slightly ajar.

You can also freeze your starter: An hour or two after feeding it, spoon it into an ice cube tray, freeze until solid, then transfer to a plastic bag. Awaken your frozen starter by placing a cube in a jar, adding 100g (½ cup) warm water and waiting until it thaws. Then stir in 100g (¾ cup) flour and wait until the starter is active again; this will take about a day, and it might need a feeding or two to really get going again.

Using the discard

The starter you remove before every feeding is called “discard” (or "unfed starter"), and it’s a shame to throw it out. Luckily, there are many ways to use sourdough discard, and we’ve compiled a bunch of suggestions here.