Maintaining your sourdough starter: food, water, and time

How’s your 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 doesn’t exactly match the process in our Baker’s Companion cookbook, nor some of our recipes online, nor 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.

Maintaining your 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:

Stir the starter well and discard all but 1/2 cup (4 ounces). Add 4 ounces non-chlorinated, room-temperature water (hereafter known simply as “water”) and 4 ounces King Arthur Unbleached All-Purpose Flour (hereafter known simply as “flour”) to the 1/2 cup of starter. Mix until smooth, and cover. Repeat every 12 hours.

A note about room temperature: 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.

For instance, try setting the starter atop your water heater, refrigerator, or another appliance that might generate ambient heat. Or, set it near a heat source (baseboard heater, etc.).

Another option: set the container of starter on a folded dish towel laid atop a heating pad on its lowest setting.


Maintaining your 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.

Take the starter out of the fridge. 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.

Remove all but 4 ounces starter. Use this “discard” to make pancakes, waffles, cake, pizza, flatbread, or another treat; Buttery Sourdough Buns is one of my favorite “unfed” sourdough recipes. Or, simply give to a friend so they can create their own starter.

Add 4 ounces lukewarm water and 4 ounces flour to the remaining starter. Mix until smooth, and cover.

Allow the starter to rest at room temperature (about 70°F) for 2 to 4 hours; this gives the yeast a chance to warm up and get feeding. After about 2 hours, refrigerate.

Getting ready to bake

If you’ve been maintaining your starter at room temperature, you may want to increase the volume of starter to the amount needed for your recipe. You can do this by feeding your starter without discarding; or by discarding, and feeding it 8 ounces flour and 8 ounces water.

If your starter has been refrigerated, you’ll want to both increase its volume, and raise its activity to a more energetic level. You can do this by giving it a couple of feedings at room temperature.

Take the starter out of the fridge, discard all but 4 ounces, and feed it as usual with 4 ounces water and 4 ounces flour. Let it rest at room temperature for about 12 hours, until bubbly. 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) starter, add 4 ounces each water and flour. If your recipe calls for 2 cups (about 16 ounces) starter, add 8 ounces 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 flour and 4 ounces water. Mix until smooth, and allow the starter to work for about 2 hours at room temperature before putting it back in the refrigerator.

Troubleshooting your starter

Living creatures sometimes get sick, be they humans, pets, or even sourdough starter. If you find yourself becoming a sourdough doctor, here are some symptoms and possible cures:

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.

Find a slightly warmer (in the mid 70s) area in which to ripen the starter after its feeding.

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.

Ripen 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.

Although 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, 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) water and a scant 1 cup (4 ounces) all-purpose flour twice a day, discarding all but 1/2 cup (4 ounces) of the starter before each feeding. 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, if your starter turns ominously pink or red; shows signs of mold growth, or smells decidedly putrid, throw it away and begin again. Luckily, in our experience, this rarely happens.

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 Extra-Tangy Sourdough Bread.

Want a printer-friendly (no photos) version of these instructions? See Feeding and Maintaining Your Sourdough Starter.

Want to make your own homemade starter from scratch? Read our post on creating your own sourdough starter.

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. pat

    In reading these posts, I am understanding that when I take my started out of the fridge, I should discard all but 4oz. Is that a cup? I understood from the directions that came with my starter to discard a cup and fed the rest. Is this discard what can be given to a friend and when do they feed it or use it?

    Pat, 4 ounces is about half a cup; let’s call it a generous half-cup. The discard can be given to a friend; they should start feeding it as soon as they get it, and feed it on a regular schedule. The discard can also be used in a number of recipes (search our recipe site using the keyword “unfed”), including the best sourdough waffles/pancakes you’ll ever taste… Enjoy – PJH

    1. Angie

      The instructions for the KAF Sourdough starter had me totally confused, so I believe I did the wrong thing in step 2…
      Once you have fed the starter and let it sit for 8-12 hours, the instructions say to stir the starter and measure out 4 ounces. Step 2 says to mix in 4 ounces of water and 4 ounces of flour, stir well, and let sit for 6 to 8 hours.
      I measured out the 4 ounces at end of Step 1, set it aside, and added the 4 ounces of water and 4 ounces of flour to the remaining starter in the bowl.

      How do I fix this situation?

    2. The Baker's Hotline

      Angie, no need to fret. While the instructions did intend for you to add the 4 ounces of flour and 4 ounces of water to the 4 ounces you measured out, your remaining starter will be just fine since you fed it the proper quantities. Just proceed with regular feedings at least once a week, discarding at least a 1/2 cup and adding back in 4 ounces of flour and 4 ounces of water. Happy sourdough baking! Kye@KAF

  2. lillabit2001

    Other than keeping your starter from taking over your fridge or kitchen counter or wherever you store it, why discard some of it before feeding it? Is it a matter of balance between the amount of starter and the amount of “food” it gets? Can a person take the starter they have been storing (I keep mine in the fridge), feed it and let it stand overnight, and then use most of the resulting sponge in a recipe as “fed” starter, then feed the remainder and put it back in the fridge after it stands for a few hours? It’s a little backwards from what you recommend, but it seems as if it would reduce the amount of starter that’s “wasted” by discarding it. I admit to trying it this way, after doing it the way you describe, and thought my results were still about the same either way.

    Also, can starter be frozen if a person anticipates not being able to use it for an extended period of time?

    I had some homemade starter many years ago, but got too busy with kids and ended up discarding it. I bought some of your starter a couple of months ago, and have been trying to use it at least once/week. I love the flavor (it’s better than my former starter) and have been enjoying trying your (and other) recipes. Love your site, your catalog and your blogs. Thanks for all you do for all of us home bakers.

    Yes, you discard some of the starter to maintain the pH balance of the whole; and to give the remaining yeast more of a chance at the food and water you’ve just added. And, as you say, there’s no need to discard the starter, if you can find something else to do with it: give to a friend or substitute it for flour/water in another recipe. Also, yes, you can do just as you recommend: feed, use most of it, feed the rest and refrigerate. In fact, that’s how I usually do it myself; the method in this post is simply another technique. All good. Freeze? Sure. Works well, so long as your freezer doesn’t drop below 0°F, which is yeast’s dying point. Best not to keep it frozen too long, though; the longer it’s frozen, the less vigorous it’ll be when it wakes up. Probably best not to freeze longer than a month. Thanks for connecting here – always a pleasure, “talking” to our fellow bakers. PJH

  3. ebenezer94

    I am sad to report that my starter is shoved in the back of the fridge in a giant peanut butter jar looking very black indeed. I really need to clean it out, but I know it’s going to be an icky task. When my son was born prematurely last year and spent 72 days in the NICU, time to manage my starter just disappeared. I’ll have to start again when he’s a bit older. Up until then I was having great fun trying out all the sourdough recipes in the whole wheat baking book (well, I hadn’t gotten to ALL of them).

    We’ll be here for you when you are ready to join the sourdough fold again – until then, Happy Baking! Irene @ KAF

  4. "Sara S"

    I am a big fan of sourdough baking, and use my KAF refrigerated starter weekly. My favorite recipe is from the 200 Anniversary Cookbook – love that you take the starter right from the fridge to make a ‘sponge’ with – and the added flexibility of starting it the night before and finishing it after work the next day. I have used that base recipe to make pizza dough, stuffed sandwiches (roast beef, goat cheese and bbq sauce – yum!), wrap around hot dog pretzel style for the kids, and of course, a lovely big rustic loaf. That recipe makes nice shaped loaves too – i.e. bunnies for Easter. If you have been thinking of making the leap to sourdough, go for it – it is very fun to bake with!

    Wraparound pretzels for hotdogs – I’m on it. How about brats? (I mean the ‘dogs, not the kids!) Thanks for the inspiration, Sara – sourdough rocks! PJH

  5. dariawalton

    I’ve left my starter for far too long before, and I find that pouring off the dark liquid yields far better results than stirring it in. I killed it once by stirring it in, and had to get a new sample from my mom to start over. Since then, I’ve left it in the fridge for months and do fine just by pouring off the dark liquid, and then giving it a feeding.

    Thanks for sharing your experience here, Daria – good to know what works for each of us, so that others can give it a try. PJH

    1. Carol Bradford

      That’s encouraging to hear. I read about stirring the liquid in after I had already poured it off. My starter was ignored in the fridge for 6 months. I poured the blackish liquid off and am hopeful that I can get the starter going again.

  6. Cody F

    ok, I have a naive question. I’ve made sourdough bread in the past and have always wanted to have started stored in the fridge for when I need to make a loaf. Here’s my question: Do I cover it in the fridge? It seems as though it would take on smells or give off smells, but I’m also afraid that putting a lid on it will kill the effect of it. What is the best way for storing it in the fridge? Lid on or off?

    Don’t worry, Cody – NO question is “naive!” Baking has so many different twists and turns, especially sourdough baking, none of us can know everything… Definitely lid on. The yeast slows way down when it’s cold, and doesn’t need a lot of air. Don’t make the lid of whatever container you use airtight, but definitely use a lid. Good luck – PJH

    1. razmatazmania

      I LOVE my KAF sour dough starter crock. I “killed” my starter the first time I tried MANY years ago and kept the crock. Got the nerve up to try again and I am glad I did (both save the crock AND get new starter). All I can say is thank you…

    2. The Baker's Hotline

      You’re very welcome! We’re glad you got up the nerve to try again too! Barb@KAF

  7. "allison@bakedoff"

    Any tips for determining what recipes will work well with an “unfed”, straight-from-the-fridge starter (besides trial and error)? I like to use the ‘discard’ starter for baking on the days I feed mine. I’ve tried some of your recipes and I’m wondering what the difference is between those recipes and the ones using fed starters.

    Allison, a fed starter will give yeast-raised baked goods a better rise; more “oomph.” A fed starter will also make somewhat lighter cakes, although there’s less of a difference there. Obviously, it’s necessary to use a good, strong, bubbling starter in recipes where it plays the main leavening role; not so necessary where there are other leaveners present. I’d go ahead and try an unfed starter in any recipe calling for starter EXCEPT for yeast breads without a significant amount of added yeast. Hope this helps – PJH

  8. juliey

    The instructions that came with the King Arthur sourdough starter that I ordered about a month ago call for adding twice as much flour as water every time you “feed” the starter (adding a cup of flour and a half-cup of water, to be exact). Is that a mistake? I was very confused but double-checked the instructions against the ones downloadable on this site with the starter. It doesn’t work very well!

    Julie, you feed the starter with equal parts flour and water BY WEIGHT – which is 1/2 cup water (4 oz.) and 1 cup flour (4 oz.). Does that help? If not, please call our bakers’ hotline, 802-649-3717 – they can help you sort this out. PJH

    1. Kathy

      The instructions that come with the starter do not make clear that it must be by weight! I had the same problem.

    2. Amy Trage

      Hi Kathy, the measurements don’t need to be by weight, though we always recommend using a scale if you do have one! ~Amy

    3. Jen Leithead

      I had the same problem also! After following the directions, making one loaf of (DELICIOUS!) rustic bread, refrigerating the remainder, then following the directions to bake another batch, the starter was so thick I couldn’t even stir it. I added water to thin it out and I think it will be fine, but I’ll try it by weight next and see if it doesn’t get so thick. Thanks!

    4. The Baker's Hotline

      Feel free to thin your starter by adding a tablespoon or two of water to get a more pancake batter consistency. Happy Baking – Irene@KAF

    5. Cookie

      Yeah, these measurements have to be weighed (except water).

      4 oz(weight) of flour is not the same as 4 oz (volume; aka fl oz) of flour. The article should make this more clear…

  9. JuliaJ

    What a timely post. I’ve tossed out some starters in the past, thinking they were too far gone–maybe I should have just tried feeding them again.

    Are starters using whole-wheat or rye flours more “active”/robust/sturdy than starters based on all-purpose flours? Do higher-protein flour, like bread flour, give a better rise than all-purpose flour? Which would produce a more “tangy” or stronger sourdough flavor?


    Julia, it’s good to start your starter with a whole grain flour, as it’s liable to have more helpful lactobacilli and wild yeast than the more “sterile” AP flour. However, Jeff Hamelman, one of our SD experts, says that unless you plan on refrigerating your starter, it’s best to feed it with AP flour – as feeding a sourdough that’s kept at room temperature with whole-grain flour will encourage it to go bad. As for bread flour, there’s no need to feed your starter with bread flour; but for a potentially higher rise, bread flour (with its additional protein/higher gluten content) is a good choice. As to how to make your bread more sour – you can try refrigerating the shaped loaf overnight before baking, as colder temps. encourage the production of acetic acid (think vinegar), which is obviously sour. You could also take the easy way out and add a pinch of sour salt (citric acid). Hope this helps – PJH

  10. Holly R

    At the point where you are taking it out of the fridge to use in a recipe, and you take a portion of it off and discard, leaving 4 oz. behind – Is there anything wrong with feeding the 4 oz. (following the directions for its weekly maintenance), AND feeding the ‘discard’ (and resting that until it’s bubbling/doubling), for use in the recipe. I always feel like I’m wasting the discard.

    Absolutely, Holly – you can feed the “discard” and have two starters going; bake with it; give it to a friend… lots of things you can do with it besides toss it. PJH

    1. scampydoodle

      what happens when a very active starter all the sudden decides it dosent want to rise anymore? is there something wrong with it?

    2. The Baker's Hotline

      Instead of using water right from the tap, feed the sourdough bottled water or tap water that’s been left at room temperature overnight. You might also feed it a couple times a day (for a couple days) to get the activity level back. Always discard and begin with 4 ounces starter adding 4 ounces flour and 4 ounces water. If this doesn’t give you the activity you seek, call our Baker’s Hotline (855-371-2253) and we’ll guide you through that process. Happy Baking! Irene@KAF

    3. TomP

      Being a product of the “great depression”, I hate wasting any food. Consequently, the discard from the sourdough starter really bothered me. However, when I realised that the 8 ounces of discarded starter exactly matched the quantity of “starter” in the KAF baguette recipe, I thought “why not?” Let me tell you, it produces great results. I used this dough first as a single loaf in the “long bread baker” and got a magnificent loaf. Not satisfied, I next split the dough in half and baked two loaves again in the long bread baker. This time a daughter claimed one loaf! This week I split the dough into thirds and baked three baguettes as the recipe directs. Outstanding!
      So, don’t throw that “discard” away, bake with it!

    4. Emily

      I am at the same point as Holly R and I just have one more question. If I feed the discard to use in a recipe because the recipe calls for more starter than I’m discarding do I need to let the fed discard sit at room temp for a certain amount of time or will it be ready to use right after I’ve fed it?
      One more question, well two 🙂 Does the starter container ever need to be cleaned? And I understand that 4 oz of started needs to be kept in a container in fridge but do I need to actually measure exactly 4 oz to be left in the crock (waiting on my ordered King Arthur crock)? Or can I just leave what is left in the crock and fed it. Not worrying if it’s exactly 4 oz.
      Thank you so much! All this Q&A is so helpful! – Emily

    5. The Baker's Hotline

      All sourdough starters that are fed need to sit at room temperature for 4-8 hours before being considered “fed starter”. You can clean your starter container as often as you feel it needs it. For the best health of your starter you should use 4 oz of starter and add 4 oz of flour and 4 oz of water. We recommend using a scale and weighting the ingredients for the best results. Hope this helps and Happy baking! JoAnn@KAF

    6. Juli

      Hi there! I’m an absolute beginner. I would like to refrigerate my starter, and I am wondering, when refrigerating for the first time, do I need to wait 2-4 hours after a feeding before putting it in the fridge?

    7. Susan Reid

      Yes, Juli, that is better for the starter. It gives the yeast a chance to get up and running before you put it away for its nap. Susan

    8. The Baker's Hotline

      Freezing is one option, but it tends to kill off all the beneficial bacteria and wild yeast that are present in the discard. Essentially you’ll be using pre-mixed flour and water if you use discard that’s been frozen, so the flavor may be less robust than what you’d hope for. Kye@KAF

    9. Carolyn sedinger

      When my starter in sitting on kitchen counter for 12 hours should I cover it with plastic wrap? How about in refrigerator?

    10. The Baker's Hotline

      We recommend keeping starters loosely covered to help prevent them from drying out. Whatever lid or cover you use should allow some gas exchange. Plastic wrap or a lid slightly ajar works well. Kye@KAF

    11. Gina Ormandy

      I made my first starter 4 days ago, at first is looked very active and seemed to double in size between feedings. I am on my second day of twice a day feedings and it doesn’t seem as bubbly or active, just seems to have stopped growing. Any suggestions? Do I just need to start over?

    12. The Baker's Hotline

      No need to start over, Gina, as long as some bubbles develop after each feeding. Keep with your regular feedings at room temperature about every 12 hours, making sure the starter is loosely covered and at a comfortable room temperature. It’s somewhat normal for the starter to go through a bit of a lull in activity after you switch from whole grain to all-purpose flour. It should pick up after a few more days, so have faith and cross your fingers. Good luck! Kye@KAF

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