Wild rosella (Hibiscus sabdariffa), is an introduced species that typically grows in the most northern parts of Australia from Cairns in the east through to Broome in the west.
The petals can be used for making jellies and dessert garnishes. They have a tart flavour with a raspberry/rhubarb/plum quality.
The young fresh leaves are great in a mixed salad, as are the chopped fruit (calyx). The older leaves make a superb curry (a common dish in SE Asia). The calyx has a myriad of uses; sun dried as a tea, made into a magnificent jam that puts strawberry in the shade, stewed and served with the morning muesli or used in tarts and puddings, and prepared as a syrup for flavouring drinks.