Steep, Simmer, Salve

Infusion and Decoction: The Two Ways an Herbal Tea Gets Made

Herbal tea is usually made one of two ways. Either hot water gets poured over the herbs and they soak for a short time, or the herbs go into a pot of water that's kept boiling on the stove. The first one is called an infusion. The second one is called a decoction (Abubakar & Haque, 2020; Ahmed et al., 2026).

What an infusion is

For an infusion, the plant material sits in water and soaks. In a hot infusion, the herbs soak in water that's just been boiled. Ahmed and colleagues also describe a cold infusion, where the herbs soak in room-temperature water for six to eight hours before they're strained out.

An infusion suits compounds that dissolve easily and come out of the plant on their own once the water reaches them (Abubakar & Haque, 2020). Flavonoids and other polyphenols, two big families of plant compounds, are among the ones an infusion pulls out into the water (Ahmed et al., 2026).

What a decoction is

For a decoction, the plant material stays in the water while it keeps boiling, usually for anywhere from fifteen minutes to an hour, depending on which part of the plant is in the pot. A decoction is the method suited to hard plant parts like roots and bark (Ahmed et al., 2026). The heat stays on the whole time, which speeds up how fast compounds move out of the plant and into the water. That makes it the right fit for compounds that dissolve in water and hold up to heat without breaking down (Abubakar & Haque, 2020).

What happens when you make the same herb both ways

In 2014, Martins and colleagues took oregano and prepared it three ways: as an infusion, as a decoction, and as an extract made with a mix of water and alcohol. Then they measured what ended up in each one.

The decoction had the highest concentration of flavonoids and of phenolic compounds overall. Phenolic compounds are a large family of plant chemicals, and flavonoids are one group within it. The infusion came second and the water-and-alcohol extract came third. The decoction also showed the strongest antioxidant activity, which is a measure of how well a substance neutralizes unstable, reactive molecules, and the researchers tied that activity to the phenolic compounds, mostly the flavonoids. The water-and-alcohol extract did best at one other job, slowing the growth of E. coli bacteria in the lab (Martins et al., 2014).

So the method you use decides what ends up in your cup. The same oregano produced three liquids with different amounts of the same compounds in them.

How you use each one

You drink both of them. The plant material gets strained out first, and what's left in the cup or the pot is the liquid that's taken on the plant's water-soluble compounds.

What each one asks of you is time. An infusion only needs the herbs to soak in hot water and then be strained. A decoction keeps a pot on the stove, and the plant material boils for fifteen minutes or more before it's strained. That's why a tea made from roots or bark takes longer to make than one you just pour hot water over.

Get the guide

My free Guide to Herbal Tea has 39 blends, each with its method, and a section on when to steep and when to simmer: kbaco.net/tea-guide

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