How to Make and Maintain Sourdough Starter

A sourdough starter is one of those things I wish I had started sooner.

I put it off for a long time because it felt complicated, all the ratios and temperatures and terminology. But once I actually did it, I realized it’s mostly just flour and water and patience. You’re not doing much. You’re just paying attention.

Now I keep a starter going year-round. It sits on the counter when I’m baking regularly, moves to the fridge when life gets busy, and I even have a dehydrated backup in case all fails! It has become one of the most useful things in my from-scratch kitchen. Every loaf of bread, every batch of waffles, every lazy Sunday morning stack of pancakes starts with it.

If you’re brand new to sourdough and not sure where to begin, my Starting with Sourdough guide walks you through the whole journey from the very beginning. And before you get started, it’s worth reading through the tools I actually use, you don’t need much, but a few things make the process easier.

This guide covers everything, how to make your starter from scratch, how to feed and maintain it, what to do if it gets sluggish, and how to store it long-term. Take it one day at a time and don’t overthink it. Your starter doesn’t have to be perfect to make really good bread.

New to sourdough? Start here → Starting with Sourdough: A Beginner’s Guide

What is Sourdough Baking?

Sourdough baking is the process of making bread using a natural fermentation method instead of commercial yeast. It relies on a sourdough starter, which is a live culture of flour and water that captures wild yeast and beneficial bacteria from the environment. Over time, this mixture ferments, creating a bubbly, tangy, and active leavening agent that helps dough rise.

Why is a Starter Essential?

A sourdough starter is what gives sourdough bread its unique texture, flavor, and digestibility. Here’s why it’s a must-have:

• Natural Leavening: Unlike store-bought yeast, a starter naturally produces the gases needed to make bread rise.
• Richer Flavor: The fermentation process develops a deep, tangy taste that you don’t get from quick-rise breads.
• No Additives or Preservatives: A starter is made from just flour and water—no need for commercial additives.
• Long Shelf Life: Properly cared for, a sourdough starter can last indefinitely (some have been kept alive for generations!).

Equipment

• Large glass jar or container: A quart-sized mason jar or similar works best. Avoid metal, as it can react with fermentation.
• Kitchen scale (optional): Helps ensure accurate feeding ratios.
• Wooden spoon or spatula: For mixing.
• Breathable cover: A clean towel, coffee filter, or loose-fitting lid.

For my full list of what I actually use, check out The Best Tools for Sourdough Baking.”

Ingredients

• Flour: any flour works to make your sourdough starter, but I like to use all-purpose flour, bread flour, or even whole wheat flour.
• Water: filtered water is essential. Chemicals and heavy metals in tap water and even some well water can hinder the success of the growth of your starter.

How to Make Sourdough Starter From Scratch

Day 1: Mixing the Starter

In a clean jar, combine ½ cup (60g) of flour and ¼ cup (60g) of water. Stir until fully combined, making a thick, paste-like consistency. Scrape down the sides and loosely cover with a breathable lid. Place the jar in a warm spot (70-75°F or 21-24°C) away from direct sunlight.

Day 2: First Signs of Activity

After 24 hours, check for small bubbles or a slightly tangy smell, this means the wild yeast is beginning to grow. Stir the mixture and add ½ cup (60g) of flour and ¼ cup (60g) of water. Mix well and loosely cover again.

Day 3-4: Feeding and Fermentation

By now, you should see more bubbles and a slightly sour or yeasty aroma. The starter may rise and fall between feedings. Continue feeding ½ cup (60g) of flour and ¼ cup (60g) of water every 24 hours. Stir well after each feeding and keep it in the same warm spot.

Day 5-6: Strengthening the Starter

Your starter should now be doubling in size between feedings and have a tangy, slightly sweet aroma. If it’s sluggish, move to twice-a-day feedings: discard half of the mixture, then feed with ½ cup (60g) of flour and ¼ cup (60g) of water.

Day 7: Ready to Use!

By day 7, your starter should be bubbly, active, and doubling in size within 4-6 hours of feeding. To test if it’s ready, perform the float test: drop a small spoonful into water, if it floats it’s ready for baking! If not, continue feeding for a few more days.

How to Maintain Sourdough Starter

A sourdough starter is a living culture that needs regular “feeding” to stay active. Feeding involves discarding a portion of the starter and replacing it with fresh flour and water. This prevents excessive acidity and maintains a balance between wild yeast and beneficial bacteria.

Standard Feeding Ratio (1:1:1)

• Starter: 1 part
• Flour: 1 part
• Water: 1 part

For example, if you have 50g of starter, you’ll mix in 50g of flour and 50g of water. This is the most common ratio and keeps the starter well-balanced.

Maintaining a Starter at Room Temperature (For Daily Bakers)

If you bake several times a week, keep your starter at room temperature and feed it once a day.

Daily Feeding Routine:

1. Discard half of the starter (or use it in a discard recipe like pancakes or crackers).
2. Feed with equal parts flour and water (by weight).
3. Stir well to fully incorporate and let it rest at room temperature (~70-75°F or 21-24°C).

Within a few hours, the starter should bubble and expand, reaching its peak in about 4-6 hours.

Sourdough Discard Recipes to Try

Don’t throw away your discard, it’s one of the most useful things in a from-scratch kitchen. Here are some of my favourite ways to use it:

Storing a Starter in the Fridge (For Occasional Bakers)

If you bake only once a week or less, you can store your starter in the fridge to slow down fermentation and reduce feedings.

Weekly Maintenance Routine:

1. Feed the starter as usual, then let it sit at room temperature for 1-2 hours.
2. Cover loosely (to allow some airflow) and place it in the fridge.
3. Once a week, remove it from the fridge, discard half, and feed it with fresh flour and water.

When you’re ready to bake, take the starter out 24 hours in advance, feed it at least twice, and wait until it’s bubbly and active before using it. A well-maintained fridge-stored starter can last a few weeks without feeding, but it may need a few extra feedings to regain strength.

Reviving a Neglected Starter

If your starter has been sitting unfed in the fridge for several weeks or months, it may have developed a dark liquid on top called hooch, a sign that it’s hungry but still alive!

How to Revive It:

1. Stir in or pour off the hooch (stirring will make it more sour, discarding will reset the balance).
2. Discard most of the starter, leaving just a small amount (about 1 tablespoon).
3. Feed it twice daily with a 1:1:1 ratio until it becomes bubbly and active again.
4. If it doesn’t respond, try switching to whole wheat or rye flour for a few feedings to encourage fermentation.
5. If your starter has mold, an off-putting rotten smell, or pink/orange discoloration, it’s best to start fresh.

Strengthening a Weak Starter

A sluggish starter might be struggling due to an imbalance of yeast and bacteria. Here’s how to bring it back to life:

• Use warm water (~80°F/27°C) to speed up fermentation.
• Feed more frequently (every 12 hours) for a few days.
• Increase the feeding ratio (1:2:2) to give it more fresh food.
• Try whole grain flour (like rye or whole wheat) for a boost.

If your starter isn’t doubling in size within 6 hours of feeding, it’s not strong enough for bread baking yet. Keep feeding until it gains strength.

Long-Term Storage (Vacation Mode)

If you need to pause sourdough baking for several months, you can store your starter in a way that doesn’t require frequent feedings.

Option 1: Drying Your Starter (Shelf Stable for Months)

1. Spread a thin layer of starter on parchment paper.
2. Let it air dry completely.
3. Break it into flakes and store in an airtight container.
4. To revive, dissolve in warm water and resume regular feedings.

Option 2: Freezing Your Starter (Short-Term Storage)

1. Feed your starter, let it bubble, then place a portion in a freezer-safe container.
2. When ready to use, thaw and resume regular feedings.

Signs of a Healthy vs. Unhealthy Starter

A healthy starter should:
✔ Smell slightly tangy, fruity, or yeasty.
✔ Double in size after feeding.
✔ Have a bubbly texture.
✔ Pass the float test (drop a spoonful into water, if it floats it’s ready to bake).

An unhealthy starter may:
✖ Smell like rotten eggs, ammonia, or mold.
✖ Have pink or orange streaks (signs of contamination).
✖ Refuse to rise even after multiple feedings.

Final Tips for Success

• Be patient. A new starter can take up to two weeks to fully mature. That’s normal. Keep feeding it and give it time.
• Save your discard. Every feeding gives you discard, don’t throw it away. Use it for pancakes, crackers, waffles, or bread. There’s a whole collection of sourdough discard recipes worth bookmarking.
• Warmth matters. If your kitchen runs cold, fermentation slows down. A warm spot, near the stove, on top of the fridge, makes a noticeable difference especially in the first week.
• Every starter is a little different. Don’t stress if yours doesn’t look exactly like photos or videos online. As long as it’s bubbling and rising, it’s working.