Guide Sourdough
Sourdough starter not rising? Here is how to fix it
If your sourdough starter will not rise, the root cause is usually temperature, feeding ratio, flour quality, or starter health. In most cases, you can recover it quickly with warm conditions and consistent feedings.
At warm room temperature (around 24C and above), King Arthur Baking notes a healthy starter often doubles within about 6 to 8 hours after feeding. In colder kitchens, it can slow down significantly.
Last reviewed: 2026-02-16
Quick answer (snippet-ready)
- Target 24C to 27C for 2 to 3 days.
- Feed consistently at 1:2:2 every 12 hours during rescue mode.
- Use 10% to 20% whole grain flour (rye or whole wheat).
- Track real rise in a straight-sided jar, not bubbles alone.
Quick diagnosis: what "not rising" actually means
- A new starter under about 2 weeks can rise early, then go quiet for several days and still be normal.
- A mature starter that suddenly stopped rising is usually too cold, underfed, or overly acidic from long gaps between feeds.
Step 1: Check safety and health first
- Discard and restart if you see pink or orange streaks, fuzzy mold, or a rotten smell.
- Gray liquid (hooch) usually means hunger, not death. Feed it on schedule.
Step 2: Fix temperature first (most common culprit)
If your room is below about 20C, activity can look dead even when the culture is viable.
Use warmer water (about 27C to 32C), and place the jar in a warm stable spot: top of the fridge, oven light on, or microwave with hot water nearby.
Step 3: Correct the feeding ratio
Ratios are by weight: starter : flour : water. 1:1:1 is equal weights.
A common failure pattern is too much old starter and too little new flour/water, creating an acidic and underfed culture.
Rescue baseline: 1:2:2 every 12 hours (example: 20g starter + 40g water + 40g flour).
If needed, use 1:4:4 when you need a slower peak or your room is very warm.
Step 4: Add nutrients (flour choice matters)
If your feed is 100% white flour and the starter is sluggish, add 10% to 20% whole grain.
Rye is often a strong accelerator and helps weak starters rebuild activity.
Step 5: Track rise correctly
- Stir down completely before feeding.
- Move to a straight-sided jar.
- Mark the level with tape or a rubber band.
- Track rise + peak + fall timing for each cycle.
3-day rescue plan (practical protocol)
- Day 1 to Day 3: keep starter at 24C to 27C.
- Feed every 12 hours at 1:2:2.
- Use 10% to 20% rye or whole wheat in the flour portion.
- Keep jar sides clean to reduce contamination risk.
- Exit rescue mode when it doubles reliably in a predictable window for 2 to 3 days in a row.
When is it strong enough to bake?
- It rises, peaks, and falls predictably.
- It at least doubles at your normal ratio and room temperature.
- It has a clean tangy/yeasty smell (not harsh solvent).
Use Sourdough Forge to stop guessing
- Log feedings (ratio, flour type, hydration).
- Track temperature and time-to-peak.
- Add smell and rise observations in your journal.
- Use reminders so rescue feedings happen on time.
FAQ
Why did my starter rise on day 2, then stop?+
Early activity can be normal in new starters. Keep temperature warm and feed consistently; many cultures stabilize after this phase.
My starter bubbles but does not rise. Why?+
Usually it is too cold, too acidic, or too thin. Warm it, feed a stronger ratio (for example 1:2:2), and track real volume rise in a straight jar.
Should I use warm water for feedings?+
Yes, especially in a cool kitchen. Water around 27C to 32C can help restore activity.
Do I need rye flour?+
Not mandatory, but adding 10% to 20% rye or whole grain often improves fermentation speed and reliability.
Related guides
Sources
Sourdough Forge
Track your starter with Sourdough Forge on the App Store.