Bring 300 ml water to the boil and cool to 80 °C for 3-4 minutes. Peel ginger and grate finely. Place in a tall mixing bowl together with tea leaves. Pour tempered water over it and let the tea steep for about 4 minutes. Pour the tea through a fine sieve and let it cool down.
Mix tea, agave syrup, gin and apple juice. Divide the ice cubes into four glasses (approx. 250 ml each). Pour the cocktail into the glasses. Garnish as desired with lime and cucumber sticks.