Buy a dried or fresh starter culture

Purchase a proven sourdough starter culture and rehydrate it at home. This is the most predictable path to a working starter — no guesswork, no false starts, and typically active within 5-7 days of feeding.

Top Options

• King Arthur Baking — Sells a fresh (not dried) starter descended from a culture maintained for decades. Ships fresh, must be fed within 10 days. Also available as a starter kit with flour and instructions. Around $10-15.
• Cultures for Health — Dehydrated heirloom cultures in multiple varieties: whole wheat, San Francisco-style, rye, and gluten-free. Takes 5-7 days to fully activate. Around $10-20.
• Etsy sellers — Many artisan bakers sell dehydrated starters with detailed rehydration instructions, often with specific heritage or regional character. $5-15.

How to Rehydrate

1. Combine the dried culture with equal parts flour and lukewarm water per the instructions
2. Feed every 12-24 hours, discarding half each time
3. Within 5-7 days the starter should be doubling reliably

Tips

• King Arthur's fresh starter is the fastest to activate — often ready in 2-3 days
• Dried starters have an extremely long shelf life and ship easily in a regular envelope
• Once rehydrated, a purchased starter adapts to your local flour and environment within a few weeks