Maintaining your sourdough starter: food, water, and time

How’s your sourdough starter doing? Fresh sourdough starter is a wonderful resource. Bread, pancakes, waffles, cake… there are so many delicious directions you can take with sourdough. The key: maintaining your sourdough starter so that it’s healthy, happy, and ready to go when you are.

Once you’ve successfully created your starter, you’ll need to feed it regularly.

If you bake a lot of sourdough treats, you may want to keep it on your counter, at room temperature. While this means feeding it twice a day, it also means your starter will be ready to bake with at the drop of a hat (er, oven mitt).

However, many of us don’t want the commitment of twice-a-day feedings. If you’re a more casual sourdough baker, it’s possible to store your starter in the refrigerator, feeding it just once a week.

Let’s take a look at both methods.

But first, a word of advice. Sourdough baking is as much art as science. This method for maintaining sourdough starter is just one of many you might choose to follow. It might not exactly match what you read in your favorite online bread forum, or what your neighbor down the street does.

And that’s OK. If you have a process you’ve successfully followed before, then hey, stick with it. Or try this one and compare. All good.

Effectively maintaining your sourdough starter is the key to great sourdough baking. See how it's done. Click To Tweet

Maintaining your sourdough starter at room temperature

Room temperature is the best environment for the yeast and lactobacilli that inhabit your starter, and you can learn a lot about your starter by observing a twice-a-day feeding regimen with the starter at room temperature.

If you’re willing to maintain your starter at room temperature by feeding it twice a day, here’s how.

Maintaining your sourdough starter via @kingarthurflour

Stir the starter well and discard all but 1/2 cup (4 ounces, 113g).

Maintaining your sourdough starter via @kingarthurflour

Add about 1/2 cup (4 ounces, 113g) room-temperature water (hereafter known simply as “water”) and a scant 1 cup (4 ounce, 113g) King Arthur Unbleached All-Purpose Flour (hereafter known simply as “flour”) to the 1/2 cup of starter.

Maintaining your sourdough starter via @kingarthurflour

Mix until smooth, and cover.

Maintaining your sourdough starter via @kingarthurflour

Note the combination of large and small bubbles, plus the uneven, somewhat “mounded” surface; this starter is ready to use.

Your starter will bubble and grow until it’s doubled (or more) in size…

Maintaining your sourdough starter via @kingarthurflour

With its flat surface and a plethora of small, foam-like bubbles, this starter is past its peak and needs to be fed again before using it in a recipe.

…then will gradually sink as it awaits its next feeding.Repeat this feeding process every 12 hours.

This whole process will take anywhere from a couple of hours to all day, depending on the health of your starter and the temperature of your house: the colder the environment, the more slowly your starter will grow. If the normal temperature in your home is below 68°F, we suggest finding a smaller, warmer spot to develop your starter.

The ideal solution is a folding bread proofer, which can be programmed to exactly 70°F, sourdough starter’s favorite temperature.

Maintaining your sourdough starter via @kingarthurflour

Absent that, I like to set starter in my cold oven with just the oven light on. Over time, the light will raise the oven’s temperature to 90°F. Since I don’t want it quite that hot, I’ll turn the light off after an hour or so —however long it takes to reach 70°F — then turn it back on again if necessary.

Maintaining your sourdough starter via @kingarthurflour

Caveat emptor: If your starter’s resting in the oven, put a reminder over your oven controls lest you inadvertently start preheating it with the starter inside! Been there, done that…

Other options: Set your container of starter atop your water heater, refrigerator, or another appliance that might generate ambient heat, or near a heat source (baseboard heater, etc.). Or place it on a folded dish towel laid atop a heating pad on its lowest setting.

Maintaining your sourdough starter in the refrigerator

For most home bakers, daily feeding is impractical; so you’ll need to store your starter in the refrigerator and feed it once a week.

Maintaining your sourdough starter via @kingarthurflour

Take the starter out of the fridge. If you’re feeding it weekly, it will probably appear a bit frothy. There may be a bit of light amber or clear liquid on top. Either drain this off or stir it in, your choice; it’s alcohol from the fermenting yeast.

Maintaining your sourdough starter via @kingarthurflour

Buttery Sourdough Buns is one of my favorite “discard” sourdough recipes

Remove all but 4 ounces (113g) starter. Use this “discard” to make pancakes, waffles, cake, pizza, flatbread, or another treat.

Or, simply give to a friend so they can create their own starter.

Add 4 ounces (113g) room-temperature water and 4 ounces (113g) flour to the remaining starter. Mix until smooth, and cover.

Allow the starter to rest at room temperature (preferably about 70°F) for 2 to 4 hours, until it shows signs of life; this gives the yeast a chance to warm up and get feeding. Once it’s started to bubble, refrigerate it.

Getting ready to bake

If your starter has been refrigerated, you’ll want to raise its activity to a more energetic level. You can do this by giving it a series of feedings at room temperature, anywhere from a couple over the course of a day to two feedings a day for several days, depending on how healthy it is.

Take the starter out of the fridge, discard all but 4 ounces (113g), and feed it as usual with 4 ounces (113g) water and 4 ounces (113g) flour. Let it rest at room temperature for about 8 to 12 hours, until bubbly.

Maintaining your sourdough starter via @kingarthurflour

Repeat as necessary, every 12 hours, until you notice the starter doubling or tripling in volume in 6 to 8 hours. That means it’s strong enough to leaven bread.

For the final feeding, make sure you add enough flour and water to use in your recipe, with a little left over to feed and maintain the starter for the next time you bake.

For instance, if your recipe calls for 1 cup (about 8 ounces, 227g) starter, add 4 ounces (113g) each water and flour. If your recipe calls for 2 cups (about 16 ounces, 454g) starter, add 8 ounces (227g) each water and flour.

Once the starter is bubbling and vigorous, remove what you’ll need for the recipe and set it aside. Feed the remaining starter with 4 ounces (113g) flour and 4 ounces (113g) water. Mix until smooth, and allow the starter to work for about 2 to 4 hours at room temperature, until it shows signs of life, before putting it back in the refrigerator.

Adjusting your starter’s flavor

If your starter lacks acidity

Feed with half whole-rye (pumpernickel) flour or whole wheat flour for a few days. The extra nutrition in the bran and germ can increase the starter’s acidity.

Be sure your starter has a chance to ripen (develop) fully before it receives another feeding; before you use it in a recipe, or before refrigerating it. An ideal feeding regimen for a starter kept at room temperature (in the low 70s) is two feedings a day at 12-hour intervals.

If your sourdough is too acidic

You may be letting the starter ripen too long before using it. Once your starter is bubbling and vigorous, it’s time to make bread, feed it again, or refrigerate until its next feeding. Don’t let it become bubbly, rise, and then fall and start to “calm down;” that’s adding acidity to its flavor. Reduce the duration of ripening as necessary.

Also, try ripening your starter in a slightly cooler area, so it doesn’t digest its meal of flour and water too quickly.

Reviving a dormant or neglected starter

Sometime you may find yourself with a starter that’s gone far too long without a feeding. Covered in a clear, dark liquid (alcohol, a by-product of yeast that’s been deprived of oxygen), the starter will lack bubbles or other signs of activity, and will have a very sharp aroma.

Maintaining your sourdough starter via @kingarthurflour

The starter may even have dry skin on top, usually gray or brown in color. Skim off and discard the skin; it’s not harmful, but will discolor your starter. Although at this point the starter appears lifeless, its microflora will spring into action again as soon as they get a few good meals.

Stir the liquid back into the starter. Discard all but 4 ounces (113g), and set the bowl or crock on the counter; you’re going to be leaving it at room temperature (at least 70°F) for awhile.

Feed the starter 1/2 cup (4 ounces, 113g) water and a scant 1 cup (4 ounces, 113g) all-purpose flour twice a day, discarding all but 1/2 cup (4 ounces, 113g) of the starter before each feeding.

Maintaining your sourdough starter via @kingarthurflour

It should soon become healthy, bubbly, and active.

Sourdough starters are hearty, and easily resist spoilage due to their acidic nature. The pH of a sourdough starter discourages the proliferation of harmful microorganisms.

However, living creatures sometimes get sick, be they humans, pets, or even sourdough starter. If your starter turns ominously pink, orange, or red; shows signs of mold growth, or smells decidedly putrid, throw it away and begin again. Luckily, in our experience, this rarely happens. But for more information see our post, Sourdough starter troubleshooting.

Maintaining your sourdough starter via @kingarthurflour

OK, after all of that — how about baking some sourdough bread? Our Rustic Sourdough Bread is a great place to start.

Or for “true” sourdough, without any added yeast, try our Naturally Leavened Sourdough Bread.

Want to make your own homemade starter from scratch? Read our post on creating your own sourdough starter. And for easy access to just about everything we’ve learned about sourdough baking here at King Arthur Flour (and are eager to share with you), see our sourdough baking guide.

PJ Hamel

PJ Hamel grew up in New England, graduated from Brown University, and was a Maine journalist before joining King Arthur Flour in 1990. PJ bakes and writes from her home on Cape Cod, where she enjoys beach-walking, her husband, two dogs, and really good food!


  1. Denise H.

    This is such an awesome blog to help me with my starter. I’ve been feeding it pretty regularly, but today opted to start an additional one to give away. Thanks for the help, King Arthur!

  2. Kathy

    Can I use KA bread flour for the sourdough recipes? And for feeding?
    I am confused when people talk about hydration and bread what does that mean to have a higher hydration?

    1. The Baker's Hotline

      Kathy, you can use bread flour for your starter and bread if that’s what you have on hand! For baking, if you’re using bread flour in place of all-purpose flour, you’ll want to increase the amount of water in your recipes by two teaspoons per cup of flour, as bread flour absorbs more liquid than all-purpose flour does. Happy baking! Kat@KAF

  3. Holly Drainer

    I’m just trying to clarify – when using the starter from the fridge, you must feed it twice at room temperature for it to be ready – is that just for yeast breads or everything? Or can you take what you want of the starter from the fridge and then go about feeding the rest – if you’re just looking for flavor like in a muffin recipe? Thanks!

    1. The Baker's Hotline

      Hi Holly! If your recipe is calling for discard or unfed starter, like in a muffin recipe as you suggested, then you won’t need to reactive the starter before using it. When your starter has been stored in the fridge, you’ll want to take it out and feed it two to three times before using it in a recipe calling for active or fed starter. You want to see that the starter is just about doubling in size and becoming bubbly between feedings. Happy baking! Morgan@KAF

  4. Ellen Lee

    I had a great sourdough starter that began as a King Arthur purchase, but it embarrasses me to admit that I recently ignored it for about four months. I was ready to reorder from KA and start over, but the “dead” starter in my fridge still smelled good and had dark amber whey (not pink or purple) that I discarded. With no expectation of revitalizing the starter, I went through the feeding process and saw a few bubbles after an overnight stay in room air. No expansion, just bubbles. I repeated the feeding process three more times over a 48-hour period. At the end of that time, the starter was frothy with bubbles and had more than doubled in volume and had that indescribable elastic “spoon feel” and the aroma of great sourdough starter. Feeding it after such a long time of neglect should not have worked, but it did. It must have had great genes!

  5. Jana

    I just started my starter adding 1/2 cup water and 1 cup flour.


    1) How long do I feed it twice a day, and do I use equal amounts water and flour in those successive feedings?

    2) I don’t use it for baking until it’s doubling in size with one feeding, correct?

    3) Can I use whole wheat flour to develop the starter?

    Thank you!

    1. The Baker's Hotline

      Hi Jana! If you’ll be keeping your starter out at room temperature, you’ll always want to feed it twice a day. Once your starter is well established (predictable in its activity), you can start storing it in the fridge and taking it out once a week to feed it. The feedings will remain the same — equal parts flour, water and starter by weight. If you’re using it in a recipe that is calling for fed or active starter, you’ll want to see that the starter is just about double in size and is bubbly in appearance before using it the recipe. In recipes that are calling for unfed or discard starter, then you can just use the discard without feeding it — in these recipes, its main purpose will be to lend flavor to the baked good, not leaven it. You certainly can use whole wheat flour to get your starter going. Best of luck and if you have any questions while on your sourdough journey, please feel free to reach out to our Baker’s Hotline folks! Morgan@KAF

  6. RK

    It took 16 days for my starter (Lulu) to double in size and I finally put it in the fridge last Tuesday. It did deflate once I put it in the fridge but it still had bubbles. I took it out a week later (yesterday) to feed the starter for the weekly feeding. I left it at room temperature and even put it in the oven with the light turned on for about 6 hours all in but it didn’t rise. It smells and looks fine and has bubbles but it’s not super bubbly and is not doubling in size. Can you confirm if this is ok or do I need to do something to revive the starter?

    1. The Baker's Hotline

      Hi RK! Usually, if it’s been in the fridge for a while, it’ll take at least 2 feedings to get it going again, so feeding it every 12 hours should help. Annabelle@KAF

    1. The Baker's Hotline

      Rita, that’s a great question! The amount of starter you use will depend on the recipe in question, but in general you’ll want to follow the guidelines laid out in our Adding sourdough to a recipe blog post. Keep in mind that naturally leavened bread can take significantly longer to rise than loaves with commercial yeast, so be sure to pad those rising times quite a bit. Happy baking! Kat@KAF

    1. The Baker's Hotline

      Rita, if you’re just using it for flavor, go for it! We wouldn’t freeze starter that you were planning to feed again to offer any leavening power, though. Kat@KAF

  7. Angie

    I currently cover my starter with a coffee filter and a rubber band on the counter. Do I need to put a lid on it to store it in the fridge or keep using the coffee filter?

    1. The Baker's Hotline

      Hi Angie! We’d suggest using a lid because we don’t want the surface of your starter to dry out. If it’s in a jar, simply screw the top on but not all the way, or, you can cover the top with a dinner plate or plastic wrap. Annabelle@KAF

  8. Laura Foran

    How long can you keep the discard in the refrigerator? I put it in on Wednesday and plan on using it this weekend.
    Thank you

    1. The Baker's Hotline

      Laura, that should be just fine! 3-4 days is just the general rule, but many people find their discards are totally okay for a week. Just check for any odd colors (pink or orange streaks indicate an infected starter that should be tossed out) and give it a sniff. If it smells like starter, you’re all set! Kat@KAF

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