I have been making kombucha for several months now. I use green or white tea, flavored with hisbiscus, peach tea or other fruity teas to the mix. Since the elderberries, and rosehips are coming in season, I wonder if adding some to my tea brew prior to straining it into the kombucha making jar would be possible and beneficial.
See the below, but basically, no raw or unripe elderberries. Also, if there is any chance of the rosehips being chewed, or cut open, remove the seeds (rose seeds are a traditional source of itching powder).