How to Feed and Maintain a Sourdough Starter

Your sourdough starter is a living culture of wild yeast and bacteria, and feeding it is the one thing you need to get right. Get it right and the starter becomes a reliable tool that produces consistent, flavorful bread. Get it wrong and you end up with a sluggish jar that never quite rises the way it should.

This guide covers the full picture: what a feeding actually does, the two main schedules (counter and fridge), ratios, how to read your starter's signals, and how to bring it back to life before you bake.

What Happens When You Feed a Sourdough Starter

Every feeding does two things at once: it dilutes the acids that have built up since the last feeding, and it gives the microorganisms fresh food (the starches in flour) to metabolize. The yeast consume those starches and produce carbon dioxide, which is what makes your starter bubble and rise. The bacteria produce lactic and acetic acids, which give sourdough its flavor.

The discard step happens before feeding, not after. You remove most of the old starter (usually keeping 20 to 50 grams) so you're not accumulating a gallon of culture in your fridge. The portion you keep seeds the next generation. Then you add fresh flour and water, stir well, and wait.

Temperature drives the speed of this cycle. At around 75°F (24°C), a healthy starter fed at a 1:1:1 ratio (starter:flour:water by weight) will peak in roughly 4 to 8 hours. At 65°F (18°C), the same feeding might take 10 to 14 hours. Knowing your kitchen temperature makes the rest predictable.

Counter Schedule vs. Fridge Schedule

How often to feed sourdough depends entirely on where you're storing it.

Counter storage means your starter lives at room temperature, which means it burns through its food supply quickly. You'll need to feed it at least once every 24 hours, and twice a day in a warm kitchen (above 78°F). This schedule makes sense if you bake several times a week and want a starter that's always at or near peak activity.

Fridge storage slows the culture down dramatically. Cold temperatures suppress yeast and bacterial activity, so the starter can go 5 to 7 days between feedings without damage. Most home bakers keep their starter in the fridge and pull it out the day before baking. Feed it, let it peak, then use it.

If you're just getting started and still figuring out your rhythm, the fridge schedule is more forgiving. Missing a counter feeding by a few hours in a warm kitchen can push your starter into an overly acidic state, while a fridge starter has much more buffer.

The Feeding Schedule at a Glance

Storage	Feeding Frequency	Typical Ratio	Starter Peaks In
Counter (~70°F/21°C)	Every 12 to 24 hours	1:1:1	4 to 8 hours
Counter (warm, 78°F+)	Every 8 to 12 hours	1:2:2	3 to 5 hours
Fridge (38°F/3°C)	Every 5 to 7 days	1:5:5	6 to 12 hrs after returning to room temp

Feeding Ratios and Amounts Explained

The ratio format is always starter:flour:water. A 1:1:1 feeding means equal parts of each by weight, which is a good default for daily counter maintenance. A 1:5:5 feeding gives the starter much more food relative to how much culture you're carrying, which slows things down, reduces acidity, and works well before refrigerating.

Here's how those ratios translate into practical amounts:

Ratio	Starter	Flour	Water	Total	Flour (cups approx.)	Water (cups approx.)
1:1:1 (daily counter)	20 g	20 g	20 g	60 g	2.5 tbsp	1.5 tbsp
1:2:2 (warm kitchen)	20 g	40 g	40 g	100 g	5 tbsp	3 tbsp
1:5:5 (fridge-ready)	20 g	100 g	100 g	220 g	¾ cup	7 tbsp
1:10:10 (long weekend)	10 g	100 g	100 g	210 g	¾ cup	7 tbsp

Weighing is always more accurate than measuring by volume, because flour compresses differently depending on how packed it is. A kitchen scale is the one tool worth owning if you bake sourdough regularly.

For flour type: unbleached all-purpose or bread flour works well for routine feedings. Adding a small amount of whole wheat or rye flour (even just 5 to 10% of the flour portion) speeds up activity because whole-grain flours contain more wild yeast food. If you're building a new starter from scratch, you can read more in our guide on how to make a sourdough starter from scratch.

How to Tell If Your Starter Is Hungry, Ripe, or Overripe

Reading your starter's state is a practical skill that takes a few weeks to develop, but there are clear markers.

Hungry (underfed): The starter has peaked and then collapsed. There's a faint or strong acetone/alcohol smell. A dried "high water line" on the inside of the jar shows where it peaked hours ago. The texture may be slightly stringy or watery. This is still a healthy starter, just past its window.

Ripe (at peak): The starter has doubled (or more) in volume since feeding. It's domed or just starting to flatten at the top. Bubbles are visible throughout, including on the sides of the jar. It smells pleasantly sour and yeasty, a bit like beer or yogurt. When you drop a small spoonful into a glass of water, it floats. This is the moment to use it for baking.

Overripe: The dome has collapsed back down, the texture is thin and runny, and the smell is sharply acidic. It will still survive, but baking with it now means a more sour loaf and possibly weaker rise. Feed it again and give it another cycle.

A common reason starters never seem to hit a clear peak is that something else is off. Check our troubleshooting guide on why your sourdough starter isn't rising and how to fix it if your culture has been sluggish for more than a few days.

Taking Your Starter Out of the Fridge Before Baking

This step trips up a lot of people. You can't pull your starter straight from the fridge and dump it into a dough. Cold starter is sluggish, and it will make your dough ferment slowly and unevenly.

The standard approach: remove your starter from the fridge the evening before you plan to bake. Let it sit at room temperature for 30 to 60 minutes to take the chill off. Then feed it (a 1:2:2 ratio works well here). Let it peak, which usually takes 6 to 10 hours at room temperature. Use it the next morning when it's domed and active.

If you want to bake the same day and forgot to take your starter out the night before, you can do two back-to-back feedings: one in the morning (1:1:1) and a second feeding 4 to 5 hours later (1:1:1 again). By the second peak, your starter should be strong enough to leaven dough. It takes more time and attention, but it works.

Store your starter in a glass jar or food-grade container that's at least three times taller than the volume of starter you keep, because it will expand. Loosely cover the top (a lid resting on but not sealed, or a cloth secured with a rubber band) so gases can escape.

Once your starter is healthy and active, you're ready to bake. Our step-by-step guide for your first sourdough loaf walks through the full bake from mixing to scoring.

Frequently Asked Questions

How often should I feed my sourdough starter?

At room temperature (68 to 75°F), feed your starter once every 12 to 24 hours. In a warmer kitchen above 78°F, every 8 to 12 hours. If you store it in the fridge, once every 5 to 7 days is enough.

What's the best flour for feeding a sourdough starter?

Unbleached all-purpose or bread flour is the standard. Whole wheat and rye flour encourage faster activity because they contain more nutrients for the wild yeast. A mix of 90% all-purpose and 10% whole wheat is a popular routine-feeding blend.

Can I use tap water to feed my starter?

Yes, in most cases. If your tap water is heavily chlorinated (strong bleach smell), let it sit uncovered for 30 minutes or use filtered water. Chlorine can slow yeast activity, but it's rarely a major issue for established starters.

What does healthy sourdough starter smell like?

A healthy starter smells tangy and slightly yeasty, somewhere between yogurt, beer, and vinegar. A sharp acetone or nail-polish-remover smell means it's overdue for a feeding but is still alive. A pink or orange tinge or a foul rotting smell (not just sour) can indicate contamination, and you'd need to start over.

Do I always have to discard before feeding?

Yes, unless you're building a brand-new starter in the first week or actively trying to grow your starter's volume. Discarding keeps the acid levels manageable and prevents you from needing to use enormous amounts of flour just to maintain the culture. The discarded portion isn't wasted: you can use it in pancakes, crackers, pizza dough, or quick breads right away.