From Dormant to Doubling: How to Rehydrate Sourdough Starter

This post may contain affiliate links. Please read our disclosure policy.

Learn how to rehydrate sourdough starter with this foolproof step-by-step guide. Transform your dried starter into an active, bubbly culture ready for baking delicious sourdough bread!

Two glass jars on a light surface; the left jar contains bubbly, active sourdough starter showing how to rehydrate sourdough starter, while the right jar holds dry starter. Both jars are about two-thirds full and set against a pale, blurred background.

🥖 Dried sourdough starter is like a sleeping giant waiting to be awakened. Whether you’ve received dried starter from a friend, purchased it online, or dehydrated your own for storage, rehydrating it properly is the key to successful sourdough baking!

My 2 Best Tips For How to Rehydrate Sourdough Starter
How to Rehydrate Sourdough Starter Recipe
How to Rehydrate A Dried Sourdough Starter
Recipe FAQs
More Sourdough Recipes To Try

My 2 Best Tips For How to Rehydrate Sourdough Starter

Temperature Matters: Keep your starter in a consistently warm spot (75-80°F is ideal). A slightly warm oven with just the light on, the top of your refrigerator, or near a heating vent work well. Cold environments will significantly slow the rehydration process.

Use Quality Water: If your tap water is heavily chlorinated, use filtered or bottled water. Chlorine can inhibit the beneficial bacteria and wild yeasts you’re trying to revive. Room temperature or slightly warm water works best for mixing.

🩷 Melissa

This gentle rehydration process has been tested countless times and works with virtually any dried starter variety.

The gradual approach ensures your starter rebuilds its strength without shocking the dormant cultures.

While the process takes about 4-7 days, it’s very forgiving. Your starter will work around your schedule, and you don’t need to babysit it constantly.

You’ll be baking amazing sourdough breads and goodies in less than a week!

No ratings yet

How to Rehydrate Sourdough Starter

By: Melissa Griffiths

Learn how to rehydrate sourdough starter with this foolproof step-by-step guide. Transform your dried starter into an active, bubbly culture ready for baking delicious sourdough bread!

Servings:

Save Pin Recipe Rate Recipe Print Recipe

Ingredients

▢ 30 grams dried sourdough starter, about 1 tablespoon

Instructions

DAY 1:

Weigh 30g of dried starter flakes and add to a glass pint canning jar. Add 50 grams lukewarm water and try to submerge all flakes by stirring a little.
Over the next two to three hours, stir the flakes every half hour or so. Eventually they will completely dissolve.
Once the flakes have disappeared, stir in 30g all-purpose flour. Cover lightly with a kitchen towel, material, or off set lid (don’t tighten it down) and let it sit somewhere warm. Leave it alone for about a day.

DAY 2:

The next day, take a look at your starter – you’re looking for small bubbles. If you see some, or lots, great! If not, no worries.
Feed your starter with 50 grams flour and 50 grams water. Don’t discard any; it’s not ready for that yet. We’re still trying to build it up. Mix well, cover lightly (I just set a lid on the top without screwing it down) and put your starter back in its warm place. Watch for more bubble activity – this could take anywhere from six to 12 hours.

DAY 3:

Repeat the set above the third day, cover lightly and let it rest in a warm place.

DAY 4:

On the 4th day discard all but 50 grams of your starter. Feed it using 100 grams water, 100 grams flour. Stir to mix well. Place, covered, in your warm spot, it will double or triple in size in roughly 3-12 hours. Your starter is now alive and healthy – time to get baking!

DAY 5:

If your starter is not doubling in 12 hours, repeat day 4 instructions on day 5 (discard and feed). It should be doubling by day 5-7. If it’s not doubling within a week, then it's time to troubleshoot! (See the notes below for more resources.)

Notes

Using Whole Wheat Flour: You can substitute whole wheat flour for all or part of the all-purpose flour, but be aware that whole wheat flour will create a more active starter that may progress faster through the rehydration stages. You might need to adjust your timeline accordingly. Whole wheat flour contains more nutrients that feed the wild yeasts and bacteria.

Don’t Rush the Discard Process: Resist the urge to discard starter before day 4. Your rehydrated starter needs time to build up its microbial population. Early discarding can set back the process significantly.

Watch for the Right Bubbles: Not all bubbles are created equal. Look for small, evenly distributed bubbles throughout the starter rather than just large bubbles on the surface. This indicates healthy fermentation activity.

Get Ready to Bake: Your starter is ready to use for baking when it consistently doubles in size within 4-12 hours after feeding and has a pleasant, tangy aroma. It should also pass the float test—a small spoonful should float in water when the starter is at peak activity.

More Sourdough Resources:

🍞 Grab your free Sourdough Starter Kit to get you set up to start baking!

🍞 Then watch these videos for sourdough starter success.

🍞 And finally grab the digital or hardcover copy of my Sourdough Made Easy cookbook with lots of recipes and tips all in one place!

🍞 You can also find loads of recipes here on the blog in the Sourdough Archives.

Nutrition

Calories: 27kcal, Carbohydrates: 6g, Protein: 1g, Fat: 0.1g, Sodium: 0.4mg, Fiber: 0.2g

Like this recipe? Rate and comment below!

How to Rehydrate A Dried Sourdough Starter

Day 1 — Initial Rehydration: Weigh 30g of dried starter flakes and add to a glass pint canning jar. Add 50 grams lukewarm water and try to submerge all flakes by stirring a little. Over the next two to three hours, stir the flakes every half hour or so. Eventually they will completely dissolve.

Once the flakes have disappeared, stir in 30g all-purpose flour. Cover lightly with a kitchen towel, material, or offset lid (don’t tighten it down) and let it sit somewhere warm. Leave it alone for about a day.

Day 2 — First Feeding: Take a look at your starter—you’re looking for small bubbles. If you see some, or lots, great! If not, no worries. Feed your starter with 50 grams flour and 50 grams water.

Don’t discard any; it’s not ready for that yet! We’re still trying to build it up. Mix well, cover lightly and put your starter back in its warm place. Watch for more bubble activity—this could take anywhere from six to 12 hours.

Day 3 — Second Feeding: Repeat the feeding from day 2, cover lightly and let it rest in a warm place.

Day 4 — Full Strength Feeding: Discard all but 50 grams of your starter. Feed it using 100 grams water and 100 grams flour. Stir to mix well. Place, covered, in your warm spot. It will double or triple in size in roughly 3-12 hours. Your starter is now alive and healthy—time to get baking!

If Needed: Days 5-7: If your starter is not doubling in 12 hours, repeat day 4 instructions (discard and feed). It should be doubling by day 5-7.

sourdough starter in a mason jar bubbly and perfect.

Recipe FAQs

How long does it take to rehydrate dried sourdough starter?

Typically 4-7 days. Most starters show signs of life by day 2-3 and are ready for baking by day 4-5. However, some starters may take up to a week depending on the age of the dried starter, ambient temperature, and flour quality.

What if my starter isn’t showing bubbles after 24 hours?

Don’t panic! Some dried starters take longer to wake up, especially if they’ve been stored for a long time. Continue with the feeding schedule as outlined. The microorganisms are likely still viable but need more time to multiply to visible levels.

My rehydrated starter smells strongly of vinegar. Is this normal?

A vinegar smell is completely normal and indicates healthy acetic acid production. This is actually a good sign that your starter is developing properly. The smell will mellow out as you continue regular feedings and the starter becomes more balanced.