Does water temperature really mater? You may have noticed we list different temperatures for different teas in our brewing instructions. Most of the time, we just think about bringing water to a full boil, but some teas are a little more delicate and can’t take the heat.
As a general guide, green teas need cooler water, around 176 degrees Fahrenheit. For white tea & roasted greens, go with 194 degrees. This 'middle ground' temperature can apply to younger raw (sheng) pu'er, and ‘jade’ oolongs (unroasted, low oxidation), but that’s a matter of preference. For everything else, 212 degrees. If those numbers seem like a pain to remember, maybe it’s time to go metric: that's 80 degrees for Green, 90 degrees for White, and 100 degrees for the rest in Celsius.
So what happens if you use the "wrong" temperature? Don't worry, the world won’t end. Hotter water speeds up the brewing, which can bring out more flavor, but can also bring bitterness, especially with Japanese green teas. If your tea is bitter, try brewing it with a lower temperature. On the other hand, water that is too cool will result in weaker tea, which you can compensate for by adjusting brew time.
This is where teas that support repeated brewings really shine: you can brew them again with a different temperature right away and compare. Using water that’s too hot or too cold won’t ‘ruin’ the leaves. Even if you’re enjoying the tea, it’s worth playing with the brewing elements like water temperature to understand their effects.
But what if you don’t have a kettle with a temperature setting? You’ve got two options: one is to boil the water and then let it cool off, often aided by pouring it into a secondary pitcher at room temperature. The other is to ‘eyeball’ it. Long before electric kettles, Chinese tea brewers described water at various stages during heating by comparing the bubbles to the eyes of various sea creatures.
‘Crab eyes’ is good for green tea: small bubbles on the bottom of the pot, some wisps of steam coming from the surface of the water.
The 90 degree middle-ground will have ‘fish eyes’; slightly larger bubbles on the bottom and tiny strands of bubbles beginning to move toward the surface, like a string of pearls.
And full boil, well we all know what that looks like.
As always, remember that these brewing guides and tips are just a place to start; a jumping off point to your tea journey. Tea is a personal experience, and you won't find your perfect cup unless you play with the elements.