Add the dried hibiscus to a quart-sized jar. Break the cinnamon stick into several pieces then add it to the jar as well. Using a vegetable peeler or a paring knife, remove the peel from the lemon and add it to the jar, too. Lastly, add your diced plums. 

Bring about a quart of water to a boil. Pour the water over the contents of the jar, filling it up to within an inch of the top. Cover the top of the jar with the lid, then allow it to infuse on the counter for 2-3 hours. I went with 3 hours because I liked the flavor better but make sure to taste it around 2 hours and use your judgement for your own taste preferences. 

Once your tea has infused, strain out all of the solids. At this point you can add a sweetener to your tea if you like. I ended up using about 2-3 tbsp of agave syrup. 

Serve your tea over ice and enjoy! You can keep leftovers in the fridge but make sure to drink them within 5 days.