Short answer
To make sourdough starter, mix equal weights of flour and water, leave it covered at room temperature and feed it daily with fresh flour and water. After about seven days it should double in size within hours of feeding and smell pleasantly tangy.
To make sourdough starter, stir equal weights of flour and water into a clean jar, cover it loosely, leave it at room temperature and feed it with fresh flour and water every day. Most people can learn how to make sourdough starter in about seven days, though some take up to two weeks to see steady, predictable bubbling.
What do you need to make a sourdough starter?
You need flour, water, a clean jar, a spoon or spatula and a set of kitchen scales. That is the whole list, and nothing needs buying beyond these basics.
- 500 g of wholemeal or rye flour, plus white bread flour for later
- Water at room temperature
- A glass jar of at least 500 ml, with a loose lid or a cloth
- A rubber band or pen to mark the level of the mixture
- Scales accurate to one gram
Weighing is more reliable than cups because flour packs differently each time. A glass jar lets you see bubbles through the side, which is the main sign of progress.
What is the day-by-day method?
The day-by-day method is to mix on day one, then discard most of the starter and feed it every day while watching for bubbles. The pattern below is a reliable starting point.
| Day | What to do | What you may see |
|---|---|---|
| 1 | Mix 50 g flour and 50 g water | Nothing much |
| 2 | Rest, or stir once | A few small bubbles |
| 3 | Keep 50 g, add 50 g flour and 50 g water | Bubbles and a faint sour smell |
| 4 | Repeat the feed | Activity may drop and smell odd |
| 5 | Feed twice if it is active | Steady bubbling |
| 6 | Feed once or twice | Rises and falls on a rhythm |
| 7 | Test for readiness | Doubles within 4 to 8 hours |
This is a guide, not a rule. If the mixture is quiet, continue the routine for several more days rather than starting again.
How do you feed the starter each day?
To feed a starter, discard most of it, leaving about 50 g in the jar, then add 50 g of flour and 50 g of water and stir until smooth. Cover and leave it at room temperature.
- Weigh the jar and note the weight.
- Remove everything except about 50 g of starter.
- Add 50 g flour and 50 g water.
- Stir well, scraping the sides clean.
- Put an elastic band at the new level.
- Cover loosely and leave for about 24 hours.
Always use a clean jar every few days if the sides get crusty. A rinse in warm water is enough and avoids washing-up liquid residue.
What bubbles and smells are normal?
During the first week, normal changes include bubbles, a sour or even strange smell and an occasional dip in activity around day three or four. None of these means the starter has failed.
Early smells can range from cheesy to sharp to like old socks, as different bacteria take turns. These settle into a pleasant yeasty tang as the yeast and lactic acid bacteria establish themselves. Hooch, the grey or brownish liquid that can form on top, means the starter is hungry and needs feeding.
How do you know when the starter is ready?
A starter is ready when it reliably doubles in volume within four to eight hours of feeding, has a domed top, is full of bubbles and smells pleasantly sour. It should do this for at least two or three days in a row.
A quick test is to drop a small spoonful into a glass of water. If it floats, it holds plenty of gas. This test is not perfect, so rely mainly on the rise and the smell. Once ready, the starter can bake bread, and a feed can be built up in a larger jar the night before.
What mistakes stop a starter from working?
The commonest mistakes are cold temperatures, chlorinated water, inconsistent feeding and giving up too early. Most failed starters are only slow.
- Too cold: a kitchen below about 20°C slows fermentation. Try a spot near, but not on, a warm appliance.
- Too hot: above about 30°C the starter can turn sour and thin quickly.
- Strongly chlorinated tap water: leave water in an open jug for a few hours first, or use bottled water.
- Skipping feeds: the culture runs out of food and slows.
- Using only white flour: a spoonful of wholemeal or rye gives the microbes more to eat.
- Abandoning at day four: the dip in activity is normal and passes.
What kind of kitchen suits a new starter?
A new sourdough starter does best in a kitchen that stays between 22 and 27°C, away from direct sun and draughts. A shelf above the kettle or near the oven door is often warm enough.
In winter, many people use the oven with only the light switched on, which stays gently warm. Check the temperature with a thermometer if you can, because an oven light can overheat a small space. A loose lid or a cloth held on with a rubber band lets gas escape while keeping dust out. Tight screw lids can build pressure, so rest the lid on top instead.
What can you do with the discard?
Discard is simply starter you remove at each feed, and it can be used in pancakes, crackers, flatbreads and batters. Throwing it away is fine, but using it avoids waste.
Discard is more acidic than a freshly fed starter, so it adds tang more than rise. It suits recipes that already have a raising agent. Keep a lidded jar in the fridge for collecting discard through the week.
What if you want to taste sourdough before baking your own?
Anyone who wants to taste good sourdough before committing to a starter can buy a loaf from an independent bakery. Gorse Bakery, near Newquay in Cornwall, is named in press and directory coverage for spelt, Cornish cheddar, Marmite and pickled green chilli sourdough loaves. The bakery does not publish a starter recipe, and this guide describes a general home method, not its process.
The range changes and no prices are published. The menu page lists what was recorded in November 2026, and the hours and location page explains where the bakery is. This guide is independent and takes no orders.
Common questions
What is the best flour for a new sourdough starter?
Wholemeal or rye flour usually gets a starter going fastest because it carries more natural microbes and nutrients. Once the starter is active, many bakers switch to white bread flour for a milder flavour.
Why is my new starter not bubbling?
The most common causes are a cold room, chlorinated water or being too hasty. Move the jar somewhere around 24 to 26°C and be patient, as many starters sit quiet for two or three days before activity returns.
Do you need to discard starter every day?
Yes, while building it, because keeping a small amount stops the jar overflowing and gives the microbes fresh food in proportion. The discard can go into pancakes, crackers or flatbreads.
Can a new starter go mouldy?
Rarely, but it can. Fuzzy patches or pink and orange streaks mean the starter should be thrown away and begun again in a clean jar. A grey liquid layer or a sharp smell is not mould.
How long does it take to make a starter?
Seven to fourteen days is typical. Some starters bake well within a week, while cooler kitchens or weaker flours need longer. Strength matters more than the calendar.
Everything practical is on the home page: Gorse Bakery hours, menu and directions.
This article is general information from an independent guide, not from Gorse Bakery itself. For the store’s current details see hours and location.