How to use the online timer
Two minutes and water well below boiling is what green tea wants, and this is where most disappointing cups come from. Boiling water scalds the leaves and drags out bitterness within seconds, which is why green tea made the way a builder's brew is made tastes harsh and astringent. Around 70 to 80°C is the target, which in practice means boiling the kettle and letting the water stand for two or three minutes, or adding a splash of cold.
Leaf quality and quantity matter more than steeping time. Delicate Japanese sencha wants cooler water and a shorter steep than a robust Chinese gunpowder, and a teaspoon of leaf in a cup is a reasonable starting point. Leaving the leaves in beyond the two minutes rarely makes the tea stronger in any useful sense; it makes it more bitter, since the pleasant compounds come out first and the tannins follow.
Good green tea will take a second and third infusion, which is one of its advantages over a teabag. Add water a little hotter and steep a little longer each time, and the character changes between cups rather than simply fading. Milk does not belong anywhere near it, and the leaves are better lifted out than left sitting in the pot between infusions.
Common questions
My green tea tastes harsh and astringent. Why?
Almost always because the water was too hot. Boiling water scalds the leaves, so let the kettle stand for two or three minutes to reach around 70 to 80°C before pouring.
Can I use the leaves again?
Yes, good green tea takes a second and third infusion. Use slightly hotter water and a slightly longer steep each time, and lift the leaves out between cups rather than leaving them in the pot.