Wash the produce well. Rinse the lemon and ginger under cool water and scrub lightly, especially if not using organic.
Slice the lemon. Cut into thin rounds. Remove visible seeds to reduce bitterness.
Prep the ginger. Peel if you like (optional) and slice thinly to expose more surface area. Thin slices infuse faster than chunks.
Add to a pitcher. Place lemon slices and ginger in a large glass pitcher or jar.
Fill with water. Pour in 6–8 cups of cold water.
Stir gently to combine.
Let it infuse. Refrigerate for at least 1–2 hours for light flavor, or up to 12 hours for a bolder, spicier infusion.
Taste and adjust. If you want a touch of sweetness, stir in 1–2 teaspoons honey or maple syrup until dissolved.
Serve. Pour over ice. Add mint or cucumber if you want an extra-cool finish.
Top off as you go. You can add more water to the pitcher once or twice before the lemon and ginger lose their punch.