So I tried again, using ground rose hip this time, which was much easier. Proportions this time:
100 ml rose hip powder
500 ml water
30 ml honey
I whisked rose hip powder into water and boiled it for a couple of minutes. The texture was less smooth than when I boiled pieces of rose hip for twenty minutes and then strained it. Soaking or maybe boiling for at bit longer might improve that.
It had much more twang now that some of the acidity is left and would probably be nice with a dollop of whipped cream. I think that a combo with dried apples would also work fine if one used less honey.