summer speed, winter patience
Kombucha brewing in different seasons
Brew consistently for a while and you'll notice your cycle changes with the seasons — because temperature plays a big role in fermentation. Here's what to expect and how to prepare for both directions.
Brewing in different seasons · Watch on YouTube
The ideal fermentation range is 73–78°F, but we obviously can't always live there. (For the deep dive, read the temperature post.)
Winter & cold-weather brewing
- Fermentation takes longer. Low temperatures make yeasts and bacteria less active. Ange's batches typically run 7–12 days around 75°F; in winter, with rooms in the high 60s, two weeks or more is normal.
- Give brews an extra dose of starter tea. A slow ferment is fine as long as mold stays away — so when the weather turns colder, Ange uses 3 cups of starter tea per gallon instead of 2. An extra dose of good bacteria and yeast, basically an immunity boost.
- SCOBYs may grow paper-thin or not at all. Cold hinders new SCOBY growth, and that's completely normal. SCOBY growth never tells you fermentation is complete — at best it confirms fermentation is happening, and fermentation can happen without it. The liquid acidifying is what matters, and the taste test is what decides doneness.
- Long ferments can taste bland. In colder months, slower batches tend toward muted flavors. Offset it in F2: bolder fruits, and more of them.
Summer & warm-weather brewing
- Warm temps = fast fermentation. Summer batches can hit Ange's preferred acidity in as little as 5 days. Taste earlier and more often so you can flavor and bottle before it goes too sour.
- Use less starter tea if batches over-shoot. Getting too sour too fast? Drop from 2 cups per gallon to 1.
- Fast ferments can taste yeasty or over-acidic. Still perfectly safe to drink — but you can offset the astringency with less starter tea, sweeter fruit juices in F2, or a little added sweet tea to rebalance.