The preparation of matcha starts several weeks before harvest and can last up to 20 days, when the bushes are covered to prevent direct sunlight. This slows down growth, stimulates an increase in chlorophyll levels, turns the leaves a darker shade of green, and causes the production of amino acids, in particular L-Theanine.
Only the finest buds are hand-picked. After harvesting, if the leaves are rolled out before drying as usual.
However, if the leaves are laid out flat to dry, they will crumble somewhat and become known as tencha (碾茶). Tencha can then be de-veined, de-stemmed, and stone-ground to the fine, bright green, talc-like powder known as matcha.