Tea Brewing
How to Make Sun Tea Safely
Sun tea can grow bacteria if you're not careful. Here's how to make it safely, plus a faster alternative that skips the risk.
Key takeaways
- The risk with sun tea is bacterial growth from hours at lukewarm temperature, not the sunlight itself.
- Refrigerate the jar in direct sun near a window, or refrigerate it after a shorter outdoor steep, to stay in a safer temperature range.
- A quick stovetop-and-fridge method gives a similar result with far less risk.
Why sun tea has a bad reputation
Traditional sun tea sits in a jar of room-temperature water for several hours while the sun gently warms it. The trouble is that lukewarm water for a long stretch is exactly the temperature range where bacteria multiply fastest.
The tea itself isn't the danger — it's untreated water sitting in that range for hours, especially in a jar that isn't fully clean or sealed.
A safer way to make it
Start with cold filtered water rather than tap water straight from a hose or an old jug, and use a very clean, tightly lidded glass jar.
- Fill a clean glass jar with cold, filtered water.
- Add about 1 tablespoon of loose leaf per quart of water.
- Set the jar in direct sun for no more than 2 to 3 hours.
- Strain out the leaves and refrigerate immediately.
- Drink within 2 to 3 days.
The 'fridge tea' alternative
If you'd rather skip any risk entirely, cold brew instead: add the same ratio of leaf to cold water and refrigerate for 6 to 12 hours rather than leaving it outside. You get the same smooth, low-tannin result without the temperature concerns.
Signs your batch has gone wrong
Cloudiness from tannins is normal and harmless, but a slimy texture, an off smell, or a batch that's been sitting out for more than a few hours should be poured out rather than risked.
Frequently asked questions
- Is sun tea actually dangerous, or is this overblown?
- For a short 2-to-3-hour steep with clean water and a clean jar, the risk is low. It rises the longer the jar sits out and the warmer the day is, which is why cold brewing is the more foolproof choice.
- Does the sunlight itself do anything to the tea?
- Not much beyond gentle warming. The flavor comes from time and temperature, not from any special effect of sunlight on the leaves.
- Can I make sun tea with tea bags instead of loose leaf?
- Yes, the same method works with bags — use about one bag per 2 cups of water and follow the same time and refrigeration guidance.
About the author
Written by the Leaf & Steep editorial team. We brew, weigh and re-test everything we publish at home with ordinary kitchen equipment — no lab, no sponsorships influencing the verdict. How we test.
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