Although the origin of tea in Japan is not clear, it is said that in the Nara/Heian era the custom of drinking tea was brought by monks from China, who also brought seeds of tea trees. As for the origin of tea trees, it is also said that there were native tea trees in Japan. Among old documents, tea was mentioned in Kigodokkyou, Kansoujirui and Koujikongen in the early Nara era. However, it is not clear whether the tea was produced in Japan or brought from China. There is a Chinese poem in Kyoukokushuu which support the hypothesis that we had native tea trees in Japan. A court lady of the Saga Emperor wrote: "she boiled the spring water and made some tea. The tea with a little bit of salt tasted better." Also there is a poem saying that the Taijou Emperor had tea with the monk Kaikou, seeing Kuukai off when he went back to the mountain. From these we can guess that the custom of drinking tea had spread among the upper-class at that time.

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Pouring hot water on green tea released its healthful constituents and flavor. Make sure to use hot, not boiling, water. Centuries of tea brewing have shown that hot water (158 degrees to 203 degrees F) brings out green tea's flavor without destroying its antioxidant power. Don't add milk: One study shows it negates green tea's health benefits. 1 tsp loose-leaf green tea per cup 1 c water per serving, plus a little extra Fill a kettle with cold water. Bring the water to a near-boil, then pour a little into a teapot to warm the pot. Swirl it around, and discard the water. Put the tea directly into the pot, or use a tea ball. One teaspoon per cup is the general recommendation, but adjust the amount of tea to taste. Fill the pot with the near-boiling water. Put the lid on the pot and infuse for 10 minutes before serving in individual cups.