Complete Guide to Making Sourdough Bread at Home

Why Sourdough Is Worth the Effort

Sourdough bread is, at its most basic, just flour, water, and salt. There is no commercial yeast, no sugar, no oil, no milk. And yet it produces a loaf with more flavour, better texture, a crackly crust, and a longer shelf life than almost any other bread you can make at home. The trade-off is time. Sourdough is not difficult, but it is slow, and it asks you to pay attention.

The flavour comes from natural fermentation. A sourdough starter is a living culture of wild yeast and lactic acid bacteria that exist naturally on grain and in the environment. These microorganisms ferment the sugars in flour, producing carbon dioxide (which makes the bread rise), organic acids (which give sourdough its characteristic tang), and a complex array of flavour compounds that commercial yeast simply cannot replicate.

This guide walks through the entire process: creating a starter from nothing, maintaining it, making your first loaf, shaping, scoring, baking, and troubleshooting the problems that every new sourdough baker encounters.

Creating a Sourdough Starter from Scratch

A starter is a mixture of flour and water that has been colonised by wild yeast and bacteria. You do not need to buy a starter or obtain one from another baker (though you can). You can create one from scratch in about 7-10 days using nothing but flour and water.

What You Need

Strong white bread flour (a small bag of wholemeal or rye flour is also useful for the first few days, as the bran contains more wild yeast and bacteria)
A clean glass jar (about 500ml capacity)
A kitchen scale
A rubber band or piece of tape to mark the level
Patience

Day-by-Day Guide

Day 1: In a clean jar, combine 50g wholemeal or dark rye flour with 50g lukewarm water (about 28-30C). Stir vigorously until smooth. Cover loosely with a cloth, a piece of kitchen paper secured with a rubber band, or the jar lid placed on top without screwing it tight. The mixture needs air exchange but should be protected from contamination. Leave at room temperature (ideally 22-26C).

Day 2: You may see a few small bubbles, or nothing at all. Both are normal. Add another 50g of flour (you can switch to strong white bread flour now) and 50g of lukewarm water. Stir well. Cover and leave.

Day 3: You should see more bubbles and the mixture may have risen slightly. It may also smell quite unpleasant: cheesy, sharp, or even like nail varnish remover. This is normal. The initial bacterial population is establishing itself, and less desirable organisms are active before the beneficial lactic acid bacteria take over. Discard half the mixture (roughly 100g) and add 50g flour and 50g water. Stir, cover, leave.

Day 4-5: Continue the daily routine of discarding half and feeding with 50g flour and 50g water. The smell should start to become more pleasant: yeasty, slightly tangy, like yoghurt or mild vinegar. Bubbles should be more consistent.

Day 6-7: The starter should now be rising noticeably between feedings, perhaps doubling in volume within 6-8 hours. The smell should be pleasantly sour and yeasty. If it is not yet rising predictably, continue the daily feeds for a few more days. Cooler kitchens will slow the process.

Day 8-10: When the starter reliably doubles in volume within 4-8 hours of feeding, it is ready to use. It should smell tangy and pleasantly fermented, and the texture should be bubbly and slightly stretchy.

The Float Test

To check if your starter is ready, drop a teaspoon of it into a glass of room-temperature water. If it floats, the starter has produced enough gas and is active enough to leaven bread. If it sinks, give it another day or two of feeding.

Maintaining Your Starter

Once established, a starter is remarkably resilient. You have two options for maintenance depending on how often you bake.

Room Temperature (for frequent bakers)

If you bake several times a week, keep the starter at room temperature and feed it daily. Discard all but 50g, then add 50g flour and 50g water. This keeps it active and ready to use at short notice.

Refrigerated (for occasional bakers)

If you bake once a week or less, keep the starter in the fridge. The cold dramatically slows fermentation. Feed it once a week: take it out of the fridge, discard all but 50g, feed with 50g flour and 50g water, leave it at room temperature for 2-3 hours until it shows signs of activity, then return it to the fridge.

When you want to bake, take the starter out of the fridge 12-24 hours beforehand and give it 1-2 feeds at room temperature to bring it back to full activity.

What to Do with the Discard

Sourdough discard (the portion you remove before feeding) is perfectly edible, it simply does not have enough rising power for bread. Use it in pancakes, waffles, crumpets, flatbreads, crackers, or pizza dough where a long rise is not critical. There is no need to throw it away.

Understanding Hydration

Hydration is the ratio of water to flour in a dough, expressed as a percentage. A dough made with 500g flour and 350g water has 70% hydration (350 divided by 500, multiplied by 100).

65-68% hydration: A relatively stiff dough. Easier to handle and shape. Produces a tighter, more uniform crumb. Good for beginners.
70-75% hydration: The standard range for most sourdough recipes. Produces a good balance of open crumb, flavour, and manageability.
78-85% hydration: Wet, slack dough that is challenging to handle but produces a very open, irregular crumb with large holes. This is what you see in high-end bakeries. Not recommended until you are comfortable with the basics.

If you are new to sourdough, start at 70% hydration and increase gradually as your confidence and handling skills improve.

Flour Choices

The flour you use has a significant impact on the bread.

Strong white bread flour is the standard base. It has a higher protein content (typically 12-14%) than plain flour, which means more gluten development and better structure. This is not optional; plain flour does not have enough protein for a good sourdough loaf.

Wholemeal flour adds flavour, colour, and nutrition. It also absorbs more water than white flour, so if you substitute wholemeal for some of the white flour, you may need to increase the water slightly. A blend of 80% strong white and 20% wholemeal is an excellent starting point.

Rye flour contributes a distinctive, earthy flavour and a denser texture. Rye contains very little gluten, so it cannot replace wheat flour entirely in a standard loaf. Using 10-15% rye in combination with strong white flour adds complexity without compromising the structure.

Spelt flour (both white and wholemeal) makes a lovely sourdough with a slightly sweet, nutty flavour. Spelt gluten is weaker than modern wheat gluten, so spelt doughs need gentler handling and shorter mixing.

The Basic Sourdough Recipe

This recipe produces one round loaf (a boule). It uses 70% hydration and assumes a healthy, active starter.

Ingredients

450g strong white bread flour
50g wholemeal flour (or use 500g all white)
350g water at about 28-30C
100g active starter (fed 4-8 hours before, bubbly and risen)
10g fine sea salt

Timeline

This is a two-day process, but the active work totals less than 30 minutes.

Day 1, Morning (08:00): Feed your starter if it has been in the fridge. Leave at room temperature.

Day 1, Evening (18:00-19:00): Mix the dough.

Combine the flour and water in a large bowl. Mix until no dry flour remains. The dough will be shaggy and rough. Cover and leave for 30-60 minutes. This rest is called the autolyse, and it allows the flour to fully hydrate and begins gluten development without any kneading.
Add the active starter and salt. Squeeze and fold the starter into the dough until fully incorporated. This is messy work; use wet hands. The dough will feel sticky and uneven at first but will come together after a minute or two of working.
Over the next 2-3 hours, perform a series of stretch and folds. Every 30 minutes, wet your hands, grab one side of the dough, stretch it upward, and fold it over to the opposite side. Rotate the bowl 90 degrees and repeat. Do this on all four sides (one set of folds). You will do 4-6 sets total. With each set, the dough will become smoother, more elastic, and less sticky. This technique develops gluten without traditional kneading and is gentler on the dough, preserving the gas that the starter has begun to produce.
After the final stretch and fold (around 21:00-22:00), cover the bowl and leave the dough to ferment at room temperature for another 1-2 hours. The dough should have grown noticeably, perhaps by 50-75%, and feel airy and jiggly. The exact timing depends heavily on your kitchen temperature. In a warm kitchen (24-26C), this will be faster; in a cool kitchen (18-20C), it may take longer.

Day 1, Late Evening (22:00-23:00): Shape the dough.

Turn the dough out onto a lightly floured worktop. Do not punch it down; handle it gently to preserve the gas.
Pre-shape by folding the edges of the dough toward the centre, then flipping it over so the seam side is down. Let it rest for 15-20 minutes, uncovered.
Final shape: Flour the top of the dough lightly. Flip it over (seam side up). Pull the bottom edge up toward the centre, then the left side, then the right side, then the top. You are creating a taut package. Flip it over again (seam side down) and use your hands to gently drag it toward you on the worktop, creating surface tension. The dough should hold its shape as a tight, round ball.
Place the shaped dough, seam side up, into a well-floured banneton (proofing basket) or a bowl lined with a well-floured tea towel. Use rice flour for dusting if you have it; it does not absorb into the dough and prevents sticking far better than wheat flour.
Cover with a plastic bag or cling film and place in the fridge. The cold retard slows fermentation dramatically and develops flavour. The dough will proof slowly overnight.

Day 2, Morning (08:00-10:00): Bake.

Baking in a Dutch Oven

A Dutch oven (a heavy, lidded cast-iron pot) is the single most important piece of equipment for home sourdough baking. It replicates the steam-injected environment of a professional bread oven. The trapped steam keeps the crust soft and pliable during the first phase of baking, allowing the loaf to expand fully (oven spring) before the crust sets and hardens.

Method

Place the Dutch oven (with its lid) in the oven and preheat to 250C. This takes at least 30-45 minutes. The pot must be thoroughly, blazingly hot.
Take the dough from the fridge. It does not need to come to room temperature. Baking it cold actually helps with scoring and oven spring.
Cut a piece of baking parchment slightly larger than the dough. Tip the dough out of the banneton onto the parchment (it should now be seam side down, smooth side up).
Score the top of the dough with a razor blade (a lame) or a very sharp knife. A single decisive slash, about 1cm deep, at a slight angle, is the classic score. The score controls where the loaf expands and prevents it from tearing randomly. Decorative scoring is popular but functional scoring is more important: the bread needs somewhere to open up.
Carefully remove the preheated Dutch oven from the oven. Remove the lid. Lift the dough by the parchment and lower it into the pot. Replace the lid.
Bake at 250C with the lid on for 30 minutes. This is the steam phase.
Remove the lid. Reduce the oven temperature to 220C. Bake for a further 15-20 minutes until the crust is deeply browned. Do not be afraid of colour. A pale loaf is an underbaked loaf. You want a rich, dark golden-brown, even bordering on mahogany in places.
Remove the loaf from the pot and place it on a wire rack. Allow it to cool completely before cutting, at least 1-2 hours. This is genuinely important. The crumb continues to set as it cools, and cutting into a hot loaf will result in a gummy, sticky interior.

Scoring

Scoring is both functional and aesthetic. The cut creates a weak point in the surface where the loaf can expand in a controlled way during the initial burst of oven spring.

Tips for Better Scoring

Use a lame (a curved razor blade on a handle) or a very sharp craft knife. A bread knife or dull blade will drag and tear the dough.
Score decisively with a swift, confident motion. Hesitation creates ragged, shallow cuts.
Angle the blade at about 30-45 degrees to the surface rather than cutting straight down. This creates an "ear" where the cut opens up and one side lifts and crisps.
Cold dough (straight from the fridge) scores much more cleanly than warm dough. This is another advantage of the overnight cold retard.

Troubleshooting

Dense, Heavy Crumb

The most common problem for beginners. Usually caused by one or more of the following:

Underactive starter. Make sure your starter passes the float test and has reliably doubled within 4-8 hours before you use it.
Underproofing. The dough did not ferment long enough. It should grow by at least 50% during bulk fermentation. In a cool kitchen, this may take 5-6 hours rather than 3-4.
Insufficient gluten development. Do at least 4 sets of stretch and folds. The dough should feel smooth, elastic, and billowy by the final set.

Flat Loaf That Spreads Sideways

Overproofing. The dough fermented too long and the gluten structure has weakened. The dough will feel soft, floppy, and may smell strongly of alcohol. Reduce bulk fermentation time or use a cooler environment.
Weak shaping. The final shape needs sufficient surface tension. Practice the shaping technique until the dough holds its form on the worktop without spreading.
Too much hydration. If you are a beginner, reduce the water by 10-20g until you are more confident with shaping.

No Oven Spring

The Dutch oven was not hot enough. Preheat for at least 45 minutes at 250C.
The dough was overproofed and had no energy left to rise in the oven.
The scoring was too shallow. The cut needs to be about 1cm deep to function properly.

Bread Is Too Sour

Reduce the time of bulk fermentation or proof.
Use a higher proportion of white flour (wholemeal and rye ferment faster and produce more acidity).
Keep the starter well-fed and use it when it is at its peak (just doubled), not after it has collapsed.
Use cooler water in the dough (24C instead of 30C) to slow down acid-producing bacteria.

Bread Is Not Sour Enough

Extend the cold retard in the fridge to 18-24 hours or even longer.
Use a higher proportion of wholemeal or rye flour.
Allow the starter to ripen a little longer before using it (past its peak but before it collapses).

Gummy Interior

The loaf was not baked long enough. Do not be afraid of a dark crust.
The loaf was cut before it cooled completely. Wait at least 2 hours.
The dough was too wet for your skill level. Reduce hydration next time.

A Few Final Notes

Sourdough is a craft that improves with repetition. Your first loaf may be imperfect, and that is entirely normal. Keep notes on each bake: the temperature of your kitchen, how long the bulk fermentation took, how the dough felt during shaping, how the finished loaf looked and tasted. These notes are invaluable for refining your process.

The beauty of sourdough is its simplicity and its depth. Three ingredients, transformed by time and wild fermentation into something that no factory can replicate. Once you have the rhythm of it, feeding the starter, mixing in the evening, shaping before bed, baking in the morning, it fits into the pattern of daily life with very little effort. And the bread itself, with its crackling crust, tangy aroma, and chewy crumb, is more satisfying than almost anything else you can make in a home kitchen.