How to Make Kombucha Sweet Tea — The Exact Ratios I Use

The sweet tea is the part of kombucha brewing that most guides treat as an afterthought. Boil water, add tea bags, add sugar, cool down, done. Move on to the interesting stuff.

But the sweet tea is the foundation of the entire batch. The strength of the tea, the amount of sugar, the steeping time and the cooling all affect the final flavour of your kombucha. Getting it consistently right makes every other part of the process easier.

This post covers the exact ratios I use, why they work, and the mistakes that are easy to make and easy to avoid.

If you want the full brewing process from start to finish, read my complete beginner’s guide. This post focuses specifically on the sweet tea stage.

The Basic Ratio

For a standard 1-litre batch (excl. starter liquid):

• 1L filtered water
• 2–4 black tea bags (or 1.5 teaspoons loose leaf)
• 75-100g white granulated sugar

That’s the foundation. Everything else is detail and adjustment.

The water is split: 500ml goes in the pot to boil and steep the tea, and the remaining 500ml goes in cold after the sugar has dissolved to bring the temperature down faster. This is a practical shortcut rather than a rule. You can use all hot water if you prefer; you’ll just wait longer for it to cool.

The Tea

Which tea to use

Black tea is the most reliable choice for beginners. It contains the tannins and nitrogen that the SCOBY culture feeds on, producing a robust, well-rounded kombucha. Assam, English Breakfast and Darjeeling all work well. Cheap supermarket black tea bags are perfectly fine; you don’t need anything expensive.

Some guides will tell you that you need loose-leaf, but in my experience, the cheap supermarket tea bags are completely fine and work well.

Green tea also works and produces a lighter, more delicate kombucha with a slightly different flavour profile. Some brewers use a blend of black and green for complexity. If you go this route, start with 70% black and 30% green and adjust from there.

When you have plenty of scobys in reserve, you can start experimenting with some other tea flavours. I have experimented with a green tea and peppermint tea blend, but I believe it tastes better when you add the fresh peppermint into the second fermentation.

I also tried white tea, which I really love and can definitely recommend trying! Just be aware that the scoby does not grow that well with it, as I have noticed.

I have also seen others experiment with hibiscus or coffee in F1. I have never tried this, but if you’re open to some experimenting, this might be a fun idea. But you probably will have to discard the scoby after a few batches.

What to avoid: Herbal teas, fruit teas, flavoured teas and anything with added oils or flavourings. Many of these contain compounds that inhibit the SCOBY or damage it over time. Earl Grey, for example, contains bergamot oil, which is particularly harmful to the culture. Stick to plain tea until your culture is well established.

How many tea bags

Two to four standard tea bags per litre is the right range. Or around 8-12 grams of tea. Two gives a lighter brew, three gives something stronger and more tannic. I use three for most batches of my batches. Mostly, I use 6g of black tea and 4g of green tea.

Loose-leaf tea gives you more control over strength. 1.5 teaspoons per litre is roughly equivalent to two standard bags. Adjust up or down based on how strong you like it.

Steeping time

Over-steeping is a more common mistake than under-steeping. For me, ten to fifteen minutes of steeping has been the sweet spot. If your kombucha consistently has a harsh or astringent edge to it, try reducing the steeping time by a minute or two. Five minutes should technically be enough to extract the flavour compounds and tannins the SCOBY needs without over-extracting the bitter compounds.

You could implement a kombucha diary and write down all the details of your batch and experiment with what you like best. A simple notes app or a physical notebook works perfectly. Just jot down your tea type, steeping time, sugar amount and fermentation days alongside a tasting note. After five or six batches patterns start to emerge.

To be honest, I have forgotten to remove my tea bags many times and the booch always turned out fine. Mostly, I let the tea steep for about 15 minutes.

Don’t squeeze the bags when you remove them. Squeezing releases additional tannins and bitter compounds that will carry through into your finished kombucha. Lift the bags out and leave them.

The Sugar

How much sugar

75–100g per litre is the optimal range that research suggests. I use 80–90g for most batches. My standard batch is 1 litre of sweet tea with 200–300ml of starter liquid added on top. Enough to give the yeast plenty to work with without making the pre-fermented sweet tea unpleasantly sweet.

The sugar isn’t just sweetness. It’s food for the yeast and bacteria in the SCOBY. Most of it gets consumed during fermentation, which is why finished kombucha is much less sweet than the sweet tea you started with. The longer you ferment, the less residual sugar remains.

Which sugar to use

Plain white granulated sugar is the right choice for your first batches and for most batches after that. The SCOBY’s bacteria and yeast are well adapted to processing sucrose. It ferments predictably and consistently every time.

A few alternatives worth knowing about once you have experience:

Raw cane sugar works well and produces a slightly more complex flavour. The SCOBY handles it comfortably. This is my personal favourite that I am brewing with most of the time.

Coconut sugar can work but ferments less predictably. Some brewers love it, others find it stalls fermentation or produces off flavours. Not recommended for beginners.

Honey is not suitable for first fermentation. Raw honey contains antibacterial properties that can harm the SCOBY culture. Pasteurised honey is slightly safer but still unpredictable. Save honey for second fermentation flavouring only.

Sweeteners (stevia, erythritol, xylitol, etc.) cannot be used in first fermentation. The SCOBY cannot ferment them. Your kombucha will not develop properly.

When to add the sugar

Add the sugar to the hot tea immediately before or after removing the tea bags, while the liquid is still hot. Hot water dissolves sugar much more efficiently than warm or cool water. Stir until every grain has dissolved before moving on. Undissolved sugar can settle and create uneven fermentation.

The Water

Use filtered water or tap water that has been left uncovered overnight. Chlorine in tap water inhibits the bacteria in your SCOBY and can slow or stall fermentation (Crum & LaGory, 2016). In areas with heavily chlorinated water, this matters more than in areas where the supply is lightly treated.

Hard water (high mineral content) is generally fine for kombucha, and some brewers believe the minerals support fermentation. Very soft water occasionally produces thinner SCOBYs, but it is not a significant problem in practice.

The Cooling Step

This is the step most often rushed, and rushing it is one of the most reliable ways to damage or kill your SCOBY.

The sweet tea must be completely cooled to room temperature before you add the SCOBY or pour it into your brewing jar. The threshold is around 30°C — above this temperature, the heat begins to damage the bacteria and yeast in the culture. At higher temperatures (above 40°C), it can kill them outright.

Room temperature cooling takes one to two hours, depending on the volume and your kitchen temperature. You can speed this up by:

Sitting the pot in a sink filled with cold water. Change the water once or twice and the tea will cool in 20–30 minutes.

Adding the remaining cold water (by splitting it as mentioned above) immediately after dissolving the sugar. This brings the temperature down significantly before you even start waiting.

Using a thermometer. If you have one, wait until the temperature reads below 25°C before proceeding. If you don’t have a thermometer, the practical test is holding your hand against the outside of the pot — if it’s comfortable to hold there for several seconds, it’s cool enough.

When in doubt, wait another half hour. A slightly longer wait costs nothing. A damaged SCOBY costs you a batch.

Scaling Up and Down

The ratio scales linearly, which makes it easy to adjust for different batch sizes:

Batch size	Water	Tea bags	Sugar
500ml	350ml	1–2 bags	30–40g
1 litre	700ml	2–3 bags	60–80g
1.3 litres (my ratio)	1L	6g black + 4g green	80-90g
2 litres	1.4L	4–6 bags	120–160g
3 litres	2.1L	6–9 bags	180–240g

Remember that these are the water volumes for the sweet tea itself. Your total batch volume will be slightly higher once you add the starter liquid.

My personal batch: 1 litre of water, 6g black tea and 4g green tea, 80–90g raw cane sugar, topped up with 200–300ml of starter liquid.

How the Sweet Tea Affects the Final Kombucha

The sweet tea you make determines the flavour foundation of your finished kombucha. A stronger tea produces a more robust, tannic kombucha. A lighter tea produces something more delicate. More sugar means more fuel for longer fermentation or a sweeter result if you harvest early.

Over time, you’ll develop preferences. Some brewers like a strong black tea base for a full-bodied result. Others prefer lighter green tea for something more subtle. The ratios here are a reliable starting point. Adjust from here based on what you like.

Common Mistakes

Squeezing the tea bags. Adds bitterness that carries through to the finished kombucha. Lift and leave.

Not dissolving the sugar fully. Stir until the liquid is completely clear. Granules of undissolved sugar at the bottom of the pot mean uneven sweetness in the batch.

Adding the SCOBY to warm tea. The most damaging mistake. Always cool completely. Always.

Using flavoured or herbal tea. Even once for an experiment. Build the habit of plain tea first and experiment with additions in the second fermentation instead.

Using the wrong water. Tap water straight from the tap in areas with high chlorination. Leave it overnight or filter it.

Frequently Asked Questions

For everything you need for your first batch, including the full step-by-step process, read my complete beginner’s guide to brewing kombucha at home.

Need help with equipment? Read the only kombucha equipment you actually need.

Sources

Crum, H., & LaGory, A. (2016). The big book of kombucha. Storey Publishing.

Jayabalan, R., Malbaša, R. V., Lončar, E. S., Vitas, J. S., & Sathishkumar, M. (2014). A review on kombucha tea — microbiology, composition, fermentation, beneficial effects, toxicity, and tea fungus. Comprehensive Reviews in Food Science and Food Safety, 13(4), 538–550. https://doi.org/10.1111/1541-4337.12072