Why Green tea goes wrong
Green tea goes wrong in the cup more often than any other category, and it is rarely the tea’s fault. The leaf is unoxidised, which means everything in it is still available to the water, including the parts you do not want.
Two groups of compounds do most of the damage. Catechins bring astringency and bitterness, and they extract quickly above 85 degrees. Amino acids bring sweetness and body, and they come out readily at 70 to 80.
That difference is the entire problem. Brew hot and long and the catechins arrive without the balance. Brew cooler and shorter and the sweetness comes first.
Most people who think they dislike green tea have only ever had it made the first way, usually in a mug with water straight off the boil.
The good news is that both mistakes share one fix, which is controlling time and temperature rather than buying better tea.
Water quality is the third variable and the one nobody mentions. Very hard water above 200 parts per million flattens the aroma, and filtered water is a cheap improvement.
Mistake 1: pouring boiling water that floods out bitter catechins
Water at 100 degrees pulls catechins out roughly twice as fast as water at 80. That is not a small difference, and it is why a delicate green made with boiling water tastes like a completely different tea.
The fix is to let the water stand. Two minutes in an open kettle brings it close to 90 degrees, and five minutes brings it to about 80.
Without a thermometer, use volume instead. Pouring from the kettle into a cold mug and then into a cup drops roughly 10 degrees each time.
Japanese greens want the lowest temperatures of all. Sencha sits near 70, gyokuro nearer 60, and both taste flat rather than better at 90.
Chinese greens are more forgiving. A pan fired Longjing at 85 is excellent, and it is one of the few greens where a slightly hotter pour does some good.
One exception is worth knowing: roasted greens such as hojicha are made for boiling water, because the roast has already removed the fragile compounds.
Mistake 2: steeping past two minutes
The second mistake is time. Two minutes is close to the practical ceiling for most green tea at a Western ratio, and four minutes produces a cup that is genuinely unpleasant.
Part of the problem is the vessel. A mug infuser leaves the leaf in the water, so the clock never stops, and by the time you have drunk half the cup the rest has over extracted.
Lift the leaf out. Decant into a second vessel or use a basket you can remove, and the tea stops changing the moment you want it to.
The Chinese method avoids the problem altogether by using more leaf and much shorter steeps. Three grams in 100 millilitres for 45 seconds, repeated eight times, never reaches the bitter zone.
That method shows you something too. Green tea changes across steeps, and the third or fourth is often the best of the session.
If you prefer the Western approach, keep to 5 grams per litre and two minutes, and pour the whole pot out when the time is up.
One more practical point: a second infusion of the same leaf is often better than the first. The leaf has opened by then, and 30 seconds on the second round gives a sweeter cup.
The habit that prevents both
Measure the water temperature once and remember what it looks like. Bubbles the size of a shrimp eye mean about 80 degrees, and a full rolling boil means 100. You will not need a thermometer after a week of paying attention.
Use a timer. Every phone has one, and guessing is the single largest source of bad green tea.
Taste at one minute. Pull the leaf earlier than you think you should, because you can always steep longer next time.
Keep the leaf out of the cup once it is done, whichever method you use.
That is the whole habit: cooler water, a timer, and the leaf removed on time. Green tea stops being difficult once those three are automatic.
If you drink green tea every day, a variable temperature kettle is the one piece of kit that pays for itself. Set it to 80 and the hardest part is already done.