Pouring active sourdough starter into a bowl

How to Activate Your Sourdough Starter, Step by Step

Activating a sourdough starter is simpler than most people expect. You need a jar, flour, water, and a few minutes a day. Here is the exact routine we teach in our workshops.

What you’ll need

  • Your ERNEY sourdough starter (live or dehydrated)
  • A clean glass jar (about 500 ml)
  • Flour — the same type as your starter (white, rye, or whole wheat)
  • Filtered or bottled water, room temperature
  • A kitchen scale (recommended, not required)

Day by day

Day 1 — wake it up

Mix your starter with equal parts flour and water (about 30 g each) in the jar. Stir well, cover loosely, and leave it in a warm spot — around 24–26°C (75–78°F) is ideal. The top of the fridge or near (not on) a warm oven works well.

Days 2–4 — feed on schedule

Once a day, discard about half the jar and feed with fresh flour and water, equal parts. Consistency matters more than precision: same time, same amounts, warm spot.

Days 3–7 — watch for the signs

You’re looking for three things:

  • Bubbles throughout the jar, not just on top
  • A pleasant tangy aroma — like yogurt with personality
  • A visible rise after feeding, often close to doubling

When all three show up reliably after each feeding — your starter is active and ready to bake.

Cool kitchen? Be patient

In cooler kitchens activation can take a few extra days. That’s normal. Warmth and consistency matter more than speed. Don’t restart — just keep feeding.

Common early mistakes

  • Chlorinated tap water can slow things down — use filtered water.
  • A sealed lid traps pressure — cover loosely.
  • Judging too early — give it at least 3–4 consistent days before you worry.

Ready to start?

Every ERNEY starter ships with full step-by-step instructions, and you can always ask questions at our free live Q&A sessions.

Get your ERNEY sourdough starter here →

Back to blog