When Your Sourdough Starter Is Ready (and How to Fix Common Problems)
When is a starter ready to bake?
A sourdough starter is ready when it’s active, predictable, and well-fed. After feeding, it should double (or more) within 4–8 hours at room temperature. You’ll see bubbles throughout, a slightly domed surface at peak rise, and a pleasant aroma—mildly tangy, bready, or yogurty. The starter should rise and fall on a regular schedule. While the float test can work, consistency and timing are better signs than any single trick.
If your starter reliably rises after feedings and smells clean and lively, it’s ready to leaven bread—even if it’s young.
Sourdough Ready Test - The sourdough float test is a quick way to see if your starter is active enough to bake with.
How to do it: Fill a glass or bowl with room-temperature water.
Gently scoop ½ teaspoon of starter from the top of the jar (that’s where the gas lives).
Drop it in the water.
What the result means
Floats → Your starter is likely active and ready to bake. 🎉
Sinks or dissolves → It’s probably not ready yet.
A few important caveats (this matters)
The float test is helpful but not foolproof.
A starter can sink and still work, especially if:
It’s very wet (high hydration)
It was recently stirred
Your flour is whole-grain or rye (heavier)
Conversely, a starter can float but be past peak.
Better indicators than the float test: If you want more reliable signals, look for:
2×–3× rise within 4–8 hours after feeding
Lots of small bubbles throughout, not just on top
A domed surface that’s just starting to flatten
A smell that’s yeasty, fruity, or lightly tangy (not sharp or boozy)
Pro baker tip
Time your bake for when the starter is at peak rise or just barely starting to fall. That’s when yeast activity is strongest.
Troubleshooting Common Starter Problems
1. Starter isn’t rising
Causes: Too cold, underfed, weak flour
Fix: Move it to a warmer spot (70–78°F), feed daily, or switch to bread flour or add a small amount of whole wheat or rye.
2. Very sour or vinegary smell
Causes: Over-fermented, hungry starter
Fix: Feed more often, increase the flour amount, or discard more before feeding.
3. Liquid on top (hooch)
Causes: Starter is starving
Fix: Stir it in or pour it off, then feed. Consider feeding more frequently.
4. Mold (fuzzy, colored growth)
Causes: Contamination or neglect
Fix: Unfortunately, discard the starter and start fresh. Clean the jar thoroughly before restarting.
5. Lots of bubbles but weak rise in dough
Causes: Starter past peak, too acidic, or dough timing off
Fix: Use the starter closer to its peak and refresh it regularly before baking.
6. Starter smells unpleasant (cheesy, rotten)
Causes: Early-stage fermentation or imbalance
Fix: Keep feeding consistently. Most starters improve within a few days of regular care.
A final reassurance
Starters are resilient. Most problems are solved with warmth, fresh flour, and patience. Learn your starter’s rhythm, feed it well, and it will reward you with flavor, strength, and beautiful bread—again and again.