Your sourdough isn't rising because your starter is too weak, your kitchen is too cold, or you're not giving it enough time

Sourdough rises through fermentation—wild yeast and bacteria in your starter eat flour and produce gas bubbles. If those bubbles aren't forming, one of three things is usually wrong: your starter isn't active enough to do the work, the temperature is too low for fermentation to happen at a normal pace, or the dough hasn't had enough time to ferment. The good news is that each of these has a straightforward fix, and you can diagnose which one by paying attention to what your dough actually does over the hours you're working with it.

The most reliable way to troubleshoot is to track three things: how your starter behaves after feeding, what your kitchen temperature is, and how long your dough has actually been fermenting. Most bakers who think their sourdough won't rise discover they either started with a weak starter or didn't wait long enough—and both are straightforward to fix once you know what to look for.

Key Takeaways

  • A weak or unfed starter is the most common reason sourdough doesn't rise—your starter should double in size within 4 to 8 hours of feeding before you use it in dough.
  • Cold kitchens slow fermentation dramatically; sourdough ferments best between 75 and 80 degrees Fahrenheit, and takes twice as long at 65 degrees.
  • Bulk fermentation (the first rise) typically takes 4 to 6 hours at room temperature, and final proof (after shaping) takes 2 to 4 hours or overnight in the refrigerator.
  • Overproofing—letting dough rise too long—looks the same as underproofing at first, but the dough will collapse in the oven instead of rising.
  • The poke test tells you if your dough is ready: press a floured finger into the dough, and if the indent springs back halfway, it's ready; if it springs back all the way, it needs more time.

Your starter may not be active enough yet

Before you mix dough, your starter needs to be at peak activity—the moment when it has just finished doubling or tripling in size after a feeding. If you use starter that's still sluggish or hasn't risen much, your dough won't rise either, because there aren't enough active yeast cells to do the work.

Feed your starter with equal parts starter, flour, and water by weight (for example, 50 grams of each). Let it sit at room temperature and watch it. A healthy starter should roughly double within 4 to 8 hours, depending on how warm your kitchen is and how long it's been since you last fed it. If your starter takes longer than 12 hours to show any rise, or if it never doubles, it's either too cold or it needs more frequent feedings to wake up.

If your starter is new (less than two weeks old), it may still be developing. Young starters ferment slowly and weakly at first. Keep feeding it daily at room temperature until it reliably doubles within 8 hours. Once it does, it's ready to use in dough. You'll know it's mature enough when the rise is consistent and predictable from one feeding to the next.

Your kitchen is probably too cold

Fermentation is a chemical process that slows down dramatically when temperature drops. Sourdough ferments best between 75 and 80 degrees Fahrenheit. At 70 degrees, fermentation takes about 50 percent longer. At 65 degrees, it can take twice as long or more. If your kitchen is 60 degrees or colder, your dough may barely rise at all in a reasonable timeframe.

You can't change your kitchen temperature when ready, but you can work around it. Place your dough in a turned-off oven with the light on, or in a cooler with a jar of warm water inside, or wrap it in a heating pad set to low. Even moving it to a warmer room—near a sunny window, or into a closet away from drafts—can make a difference. If you're in a cold climate, consider doing your bulk fermentation (first rise) overnight in the refrigerator instead of at room temperature. This slows fermentation to a manageable pace and actually improves flavor.

A straightforward way to track this: note the temperature of your kitchen and the time you mixed your dough, then check how much it has risen after 3 hours. If it has barely moved, temperature is likely the culprit. Warm the dough slightly and give it more time, or move it to a warmer spot. You can also use an inexpensive thermometer to measure the actual temperature inside your oven or proofing box.

You may not be waiting long enough

Sourdough fermentation is not fast. Bulk fermentation—the first rise, when the dough is in a bowl—typically takes 4 to 6 hours at room temperature (around 75 degrees). If your kitchen is cooler, add 2 to 4 more hours. After you shape the dough, final proof (the second rise) takes another 2 to 4 hours at room temperature, or 8 to 16 hours in the refrigerator.

Many home bakers expect their dough to rise in 2 to 3 hours and assume something is wrong when it doesn't. Sourdough is slower than commercial yeast bread because wild fermentation is gentler and produces better flavor. If your dough is rising at all—even slowly—it is working. Give it time. The difference between a dough that rises in 4 hours and one that rises in 8 hours is often just kitchen temperature, not a problem with your technique.

Use the poke test to know when your dough is actually ready, rather than watching the clock. Flour your finger and poke the dough gently about half an inch deep. If the indent springs back slowly and leaves a slight dimple, the dough is ready to shape or bake. If it springs back when ready, it needs more time. If it doesn't spring back at all and stays dented, it may be overproofed.

Your dough might be overproofed

Overproofing—letting dough ferment too long—is the opposite problem, but it looks similar at first. An overproofed dough rises well during fermentation, but then collapses or spreads flat in the oven instead of rising further. The gluten structure has broken down from too much fermentation, and the dough can't hold the gas bubbles anymore.

If your dough rises beautifully in the bowl but then doesn't rise in the oven, or if it spreads sideways instead of up, overproofing is likely the cause. The fix is to shorten your fermentation times. Start checking your dough earlier using the poke test, and move it to the oven when the indent springs back halfway rather than waiting for it to look very puffy.

Refrigerator proofing (final proof in the fridge overnight) is actually a good way to avoid overproofing, because cold fermentation is much slower. You can leave shaped dough in the fridge for 12 to 24 hours without overproofing it, and you'll have more control over when you bake. This method also gives you flexibility—you can bake whenever you're ready, rather than being tied to a specific window of time.

Check your flour and water ratio

If your starter is active, your kitchen is warm, and you've waited long enough, the problem might be in your dough itself. Sourdough dough that is too stiff (too much flour relative to water) will rise slowly or not at all, because the gluten network is tight and doesn't stretch easily. Dough that is too wet will spread instead of rise, and may not hold its shape.

Most sourdough recipes call for a hydration level between 75 and 85 percent—that means the weight of water is 75 to 85 percent of the weight of flour. A dough at 75 percent hydration will feel fairly stiff; at 85 percent it will feel sticky and loose. If you're mixing by feel rather than by weight, aim for a dough that is soft and slightly tacky but not soupy. It should hold together when you stretch it gently.

If you've been adding flour by the handful or cup, try weighing your ingredients instead. A cup of flour weighs different amounts depending on how you scoop it, and this small difference adds up. A kitchen scale costs $15 to $30 and removes this guesswork entirely. Once you start weighing, you'll notice your fermentation times become much more consistent from one bake to the next.

Your starter may need more frequent feeding

If your starter is stored at room temperature and you only feed it once a week, it may be too weak to ferment dough reliably. A starter that sits unfed for days becomes dormant and sluggish. It will eventually wake up, but it takes time and multiple feedings.

If you bake sourdough regularly, keep your starter at room temperature and feed it once or twice a day. If you bake less often, store your starter in the refrigerator and feed it once a week. Before you use it to make dough, take it out, feed it, and let it come to peak activity (usually 4 to 8 hours) before mixing.

A starter that has been in the refrigerator for weeks may take 2 to 3 feedings at room temperature before it's active enough to ferment dough properly. This is normal. Keep feeding it daily until it reliably doubles within 8 hours, then use it. You'll notice the rise becomes faster and more vigorous with each feeding as the yeast population wakes up.

Frequently Asked Questions

How do I know if my starter is dead?

A dead starter shows no signs of life after 2 to 3 weeks of daily feeding at room temperature. A living starter will eventually show bubbles, a sour smell, or a layer of liquid on top, even if it's been neglected. If your starter smells like nail polish or acetone, it's alive but very hungry—feed it daily for a week.

Can I speed up sourdough fermentation?

Yes, by warming your dough. Place it in a turned-off oven with the light on, or use a heating pad on low. You can also use a slightly warmer starter or add a tiny pinch of when ready yeast to your dough, though this changes the flavor slightly. The trade-off is that faster fermentation produces less complex flavor than slow fermentation.

What if my dough rises in the bowl but doesn't rise in the oven?

This usually means the dough was overproofed before baking. The gluten has weakened and can't trap new gas as the oven heats up. Shorten your fermentation times next time, and use the poke test to know when to bake. You can also try baking at a slightly higher temperature to set the crust faster.

Should I use warm water to speed things up?

Warm water (around 80 degrees) will speed up fermentation slightly, but cold water (around 65 degrees) will slow it down and give you more control. Most bakers use room-temperature water and adjust fermentation time based on kitchen temperature instead. This is more predictable than trying to control temperature through water alone.

How long can I leave sourdough in the fridge?

Shaped dough can stay in the refrigerator for 12 to 24 hours without overproofing. Some bakers leave it for up to 48 hours, though flavor and rise may suffer slightly. Bulk dough (unshaped) can ferment in the fridge for 24 to 72 hours. Cold fermentation is slow and forgiving, which is why many bakers prefer it to room-temperature proofing.