Bring 4 cups water to boil. Place the hibiscus and maple syrup in a carafe or heatproof bowl and pour the hot water over. Steep the hibiscus for 15 minutes.
Strain the tea mixture. Add the remaining cold water, lemon juice, and vodka (if using). Chill until ready to serve.
Pour the Arnold Palmers over ice and garnish with lemon zest and wedges.
Notes
If you're adding booze, you may want a little more maple syrup. I tried to make these healthier by keeping the sweetness to a minimum.