The short version
If you read nothing else on this page, read these four.
- 1
Keep the jar in the fridge
You only need to feed it every 2–4 weeks. Daily feeding is for bakeries, not for you.
fine print
Cold slows the yeast right down. Many starters survive far longer than four weeks between feeds — this is a hardy thing, not a fragile one. - 2
A night or two before baking, feed it
Take some out, mix 1 part starter with 2 parts flour and 2 parts water, and leave it on the bench.
fine print
20g starter, 40g flour, 40g water is a good size. Discard the rest of the old starter, or save it for crackers. Discarding isn't waste — without it the jar grows huge and the yeast never gets enough fresh food. - 3
Wait for it to double
Bubbly, domed on top, about twice the level you fed it to. That's when it's strong enough to raise a loaf.
fine print
At room temperature that's roughly 6–8 hours. Mark the jar with a rubber band or a marker pen when you feed it, so you can actually see the rise rather than guessing. - 4
Use 100g, feed the rest, back in the fridge
That's the whole cycle. Repeat whenever you want to bake.
fine print
Keep 150–200g on hand when you're planning to bake, so there's enough to use and enough left over to keep going.
The cycle
Every feed goes through the same four stages
Your starter rises, peaks and sinks back down on repeat. Learning to read where it is in that cycle is most of the skill — the rest is just waiting.
Just fed
Thick, smooth and flat. Nothing happening yet.
Mark the level on the jar so you can see the rise.
Rising
Bubbles appear through the sides, and the top starts to lift.
Nothing to do. This is the yeast getting to work.
At its peak
Roughly doubled, domed on top, and full of bubbles.
Use it now — or refrigerate to hold it here.
Collapsed
Sunk back down with a flat or dipped top.
Still fine for crackers or pancakes. Feed it before baking bread.
Try it
How the feeding ratio changes the timing
More food takes longer to get through. That’s the whole idea behind ratios: you’re not making the starter stronger, you’re choosing when it will be ready. Pick a feed and watch the curve move.
The standard feed. Everyday maintenance, and overnight or fridge storage.
At 22°C a 1:2:2 feed peaks in about 8 hrs. Temperature moves this more than anything else you can control.
- Looks like
- Thick, smooth and flat. Nothing happening yet.
- Smells
- Milky, like raw dough.
- Do
- Mark the level on the jar so you can see the rise.
Why does more food mean a slower rise?
So which one should I use?
Peaked before you’re ready? Put it in the fridge.
This is the single most useful trick for fitting sourdough around a normal life. The cold holds the starter near its peak instead of letting it rise, exhaust itself and collapse on the bench while you’re out. You are not obliged to bake the moment it doubles.
Taking it back out
Sourdough Starter — Feeding Guide
Keeping the jar alive without it running your life
How to feed your starter, how to read when it's ready, and what to do when it peaks before you are. Written for fridge storage and occasional baking, not daily devotion.
Method
Tap a step to tick it off as you go.
If it's doubled and you're not ready to bake
Put it in the fridge. The cold slows fermentation right down and holds the starter near its peak for you, instead of letting it rise, exhaust itself and collapse on the bench while you're out.
Take it back out and let it come up to room temperature before you mix your dough. If it's been in there more than a day or two, give it a fresh feed and wait for it to become active again first.
This is the single most useful trick for fitting sourdough around a normal life — you're not obliged to bake the moment it peaks.
Feeding ratios
Written as starter : flour : water, by weight.
| Ratio | Example | When to use it |
|---|---|---|
| 1:1:1 | 20g starter + 20g flour + 20g water | Ferments faster. Good in cooler weather, or for a medium activity level at room temperature. |
| 1:2:2 | 20g starter + 40g flour + 40g water | The standard. Slower rise, good for overnight and fridge maintenance. |
| 1:3:3 | 20g starter + 60g flour + 60g water | Slows fermentation slightly. Great in warm weather. |
| 1:4:4 or higher | 20g starter + 80g flour + 80g water | For a weak, acidic or long-neglected starter. Gives the yeast plenty of fresh food to rebuild strength. |
What feeding looks like
After a feed the starter thickens, then gradually becomes bubbly, rises, and forms a domed top. At peak it's airy and strong. Eventually it collapses, which means it's hungry again — but it's still perfectly usable at that point for crackers or pancakes.
Fridge storage and low-maintenance care
- Keep the starter in the fridge if you only bake occasionally.
- Feed it every 2–4 weeks ideally, though many survive far longer than that.
- Before baking, take some out, feed it, let it get bubbly and doubled, then use it.
- Even badly neglected starters — 8 to 10 weeks or more — can usually be revived by taking a small amount and feeding it large amounts of flour and water, repeatedly at 1:4:4.
How to tell it's ready to bake
- It has doubled, or nearly tripled
- Full of bubbles
- Smells mildly yeasty or slightly fruity
- Optionally, it passes the float test — a spoonful floats in water
How long it takes to rise
Temperature makes an enormous difference. These are estimates.
| Temperature | Approximate time to double |
|---|---|
| 10°C (cold fridge door) | 24–48 hours |
| 15°C (cool room) | 12–24 hours |
| 20°C (mild room temperature) | 8–12 hours |
| 22–24°C | 6–8 hours |
| 25–28°C (warm kitchen) | 3–6 hours |
| 30°C+ | 2–4 hours, but it risks over-acidity if left too long |
If it's gone too acidic
Signs: a very sour, sharp vinegar or nail-polish smell; it turns runny or separates with a layer of hooch on top; it rises poorly or not at all.
The fix: take a small spoonful only and discard the rest, feed at a high ratio like 1:4:4 or 1:5:5, and repeat every 12–24 hours until it's bubbly and strong again.
The simple routine
- Keep the starter in the fridge.
- One or two nights before you want to bake, take some out, feed it 1:2:2, and leave it at room temperature.
- Once it's doubled and bubbly, use 100g in your recipe.
- Feed the leftovers and return them to the fridge.