Feeding your sourdough starter seems simple enough—flour, water, stir, repeat. But if you've ever wondered why your starter sometimes doubles enthusiastically and other times barely budges, or why your bread has unpredictable results, the answer often lies in your feeding schedule. Your starter is a living ecosystem, and like any living thing, it thrives on consistency and timing.
Understanding Your Starter's Metabolism
Think of your sourdough starter as a miniature fermentation factory. The wild yeast and lactic acid bacteria in your jar are constantly consuming the sugars in flour, reproducing, and producing carbon dioxide, acids, and flavor compounds. But this activity follows a predictable curve. After feeding, there's a lag phase while the microbes adjust. Then comes rapid growth and gas production (the rising phase), followed by a peak, and eventually a decline as food runs out and waste products accumulate.
The key to a healthy starter isn't just feeding it—it's feeding it at the right point in this cycle. Feed too early, and you're diluting an actively growing culture before it reaches its full potential. Feed too late, and you're letting the pH drop too low and allowing less desirable bacteria to take hold. The sweet spot? Right at or just after peak rise, when your starter has roughly doubled and is just beginning to show signs of falling.
Room Temperature vs. Refrigeration: Two Different Schedules
If you keep your starter at room temperature (around 70-75°F), it's like keeping the fermentation engine running hot. Your starter will typically need feeding every 12-24 hours, depending on the ratio of starter to fresh flour and water you use. A 1:1:1 ratio (equal parts starter, flour, and water by weight) might peak in 8-12 hours, while a 1:5:5 ratio can sustain your starter for a full 24 hours before it needs attention.
Refrigeration, on the other hand, dramatically slows down the metabolism of your microbial community. A well-fed starter can coast in the fridge for a week or even two before it needs refreshment. This is perfect for weekend bakers or anyone who doesn't want the commitment of daily feedings. Just remember: when you pull a cold starter from the fridge, it needs a couple of room-temperature feedings to wake up and regain full strength before it's ready to leaven bread.
The Feed Ratio Makes All the Difference
Here's where things get really interesting. The ratio of starter to fresh flour and water you use determines how long your feeding interval should be. It's like adjusting the fuel supply to your fermentation engine.
A 1:1:1 feed (20g starter + 20g flour + 20g water) creates a dense microbial population with relatively less food. These cultures ferment quickly and peak in 4-8 hours at room temperature. This schedule is great if you're baking frequently and want a very active, tangy starter.
A 1:5:5 feed (20g starter + 100g flour + 100g water) dilutes the population significantly, giving each microbe more food to work with. This culture will take 12-24 hours to peak. It's ideal for once-daily feeding or for building a milder-flavored starter with less acidity.
The most extreme version is a 1:10:10 feed, which some bakers use when they want to stretch the interval even longer or prepare for refrigeration. This can take 24 hours or more to peak at room temperature.
Signs Your Schedule Isn't Working
Your starter will tell you if the timing is off. A starter that consistently smells overly sour or vinegary, develops a layer of dark liquid (hooch) on top, or has a grayish color is being underfed—the interval between feedings is too long, or your ratio is too starter-heavy for your environment.
Conversely, if your starter never seems to rise much or smells bland and yeasty without developing that characteristic tang, you might be feeding it too frequently or using such a high feed ratio that it never has time to develop character.
Finding Your Perfect Rhythm
The best feeding schedule is the one that fits your life and produces the results you want. Start by observing your starter closely for a few feeding cycles. Use a rubber band or piece of tape to mark the starting level after feeding, and note how long it takes to double. Check the aroma—it should be pleasantly tangy and slightly yeasty, not harsh or acetone-like.
Once you know your starter's timeline, you can adjust your ratio to match your schedule. Bake on Saturday mornings? Feed Friday night with a 1:5:5 ratio. Home all day and want maximum flavor? Try 1:2:2 feedings twice a day. Going on vacation? Give it a generous 1:10:10 feed and tuck it in the fridge.
The Weekend Baker's Strategy
For those who only bake on weekends, I recommend this approach: Keep your starter in the fridge all week. On Thursday night, pull it out and give it a room-temperature feeding at 1:5:5. Friday morning or evening (depending on your starter's speed), feed again. By Saturday morning, you'll have a vibrant, peak-condition starter ready to build into a levain for baking. After you've taken what you need for your dough, feed the remaining starter and return it to the fridge until next week.
Temperature's Hidden Role
Remember that temperature is the invisible hand controlling your feeding schedule. A starter at 65°F might take 16 hours to peak with a 1:5:5 feed, while the same starter at 78°F could peak in 8 hours. Summer and winter will require different approaches. I keep a simple thermometer near my starter and note how timing shifts with the seasons. In my cool kitchen in January, I use slightly higher feed ratios. Come July, I dial them back or switch to cooler water for mixing.
The Bottom Line
There's no single "correct" feeding schedule for sourdough starter—there's only the right schedule for your starter, your environment, and your lifestyle. Pay attention to the signs your culture gives you, understand the relationship between feed ratio and fermentation time, and don't be afraid to experiment. Once you find that rhythm, your starter will reward you with consistent rises, complex flavors, and bread that turns out beautifully every single time.
Your starter is remarkably adaptable. It's survived thousands of years of human bread-making in vastly different conditions. With a little observation and fine-tuning, you'll find the feeding schedule that makes both you and your microbial partners happy.