Hibiscus flowers (Hibiscus sabdariffa) are giving on wool and silk beige to purple, depending on mordant and processing.
With classic alum - tartar mordant and a color 1: 1 (100g material, 100g hibiscus) you'll reach a slight purple hue, which can also be intensified by reinserting.
One should also like to try to change the ph-value of the water, this also changes the color.
Potash as an addition to the dye gives a rather greyish-greenish tone.
Not suitable for consumption.