How to Feed a 1:2:2 Sourdough Starter Ratio to Make 90g (Same-Day 6 - 8 hrs Peak)
Fast same-day levain build math to make 90g of active starter (100% Liquid) using a 1:2:2 feeding ratio.
A 1:2:2 refresh for 90g splits the jar into 5 equal units of 18.0g — 18g ripe seed, 36g fresh flour, 36g water. Those three weights total exactly 90g, and the culture reaches a full dome in 6 - 8 hrs at 75°F. Building 110g instead (22g / 44g / 44g) leaves the 20g jar reserve so nothing is ever thrown away. Best for: Balanced 6–8 hour morning levain build.
- Exact 90g Build
- 18g : 36g : 36gStarter : Flour : Water (1:2:2)
- 90g + 20g Jar Reserve
- 22g : 44g : 44gBuilds 110g total (0g discard waste)
- Estimated Peak Window
- 6 - 8 hrsAt 74°F–76°F (23.5°C–24.5°C)
- Levain Hydration
- 100%Balanced 6–8 hour morning levain build
90g 1:2:2 Feeding Neighbourhood: Seed, Flour, Water & Peak Window
Peak ripening estimates assume a 75°F kitchen and 23°C room; colder kitchens need roughly 3.8% more time per degree.
| Build This Much | Seed (1 Part) | Flour (2 Parts) | Water (2 Parts) | Ripening Time |
|---|---|---|---|---|
| 70g 1:2:2 levain [Target] | 14g seed culture | 28g flour | 28g water | peak 6 - 8 hrs |
| 90g 1:2:2 levain One Step Down | 18g seed culture | 36g flour | 36g water | peak 6 - 8 hrs |
| 110g 1:2:2 levain One Step Up | 22g seed culture | 44g flour | 44g water | peak 6 - 8 hrs |
| 80g 1:2:2 levain Two Steps Down | 16g seed culture | 32g flour | 32g water | peak 6 - 8 hrs |
| 100g 1:2:2 levain Two Steps Up | 20g seed culture | 40g flour | 40g water | peak 6 - 8 hrs |
Custom Batch Recalculation Engine
Fine-tune starter hydration between 50% stiff and 125% liquid while keeping your starter feeding ratio × target weight ratios locked.
Fast Same-Day Kinetics: Why a 1:2:2 Ratio Peaks in 6 - 8 hrs (90g Build)
Because the 90g build holds only 18g of live culture, the 36g of flour and 36g of water must supply everything the yeast needs to reach a 6 - 8 hrs peak. Underfeeding therefore produces a sour sourdough culture, while a correctly fed 1:2:2 jar domes within hours.
Hydration discipline at 100% Liquid means the 36g of water should be room temperature, not hot. Water above 95°F can shock the lactobacilli and stall the 6 - 8 hrs peak, while water below 60°F pushes fermentation into a slow acidifying phase that flattens the eventual rise.
Zero-Discard Scraping Method for 90g Levain (1:2:2)
- Reserve the 20g Jar Remainder (22g): Tip your starter jar and scrape every last gram into a clean vessel — roughly 22g — so nothing is discarded.
- Combine the 1:2:2 Feed (44g + 44g): Stir 44g of flour into 22g of seed, then add 44g of room-temperature water until no dry flour remains.
- Mark the 110g Target: Level the jar and tape a line at the starting height; the culture should dome well past it within 6 - 8 hrs at 75°F.
- Harvest 90g and Return 20g: Pour 90g of peaked levain into your dough, then scrape the surviving 20g back into the jar and refrigerate at 38°F.
Technical Q&A: How to Feed a 1:2:2 Sourdough Starter Ratio to M
Can I scale this 90g build up to 180g?
Double every number: 36g starter, 72g flour, 72g water. The ratio, and therefore the 6 - 8 hrs peak, is unchanged.
Why is my 1:2:2 starter not doubling?
Usually the seed was neglected in the refrigerator. Two warm 1:2:2 refreshes at 76–78°F, each with 36g of fresh flour, will strip the acid and restart the yeast.
What happens if I use 1:2:2 starter in a very wet dough?
The 100% Liquid levain carries less acid, so a wet dough keeps more of its elasticity. Hold back a little extra water if your flour absorbs like 36g of bread flour does.