Which garden plant reflects pH of the soil in the colour of its flowers?

hydrangeas will show pink or blue if acidic, just like litmus paper

Which garden plant reflects pH of the soil in the colour of its flowers?
pj is correct, blue = acidic, pink = alkaline
Reply:Some hydrangeas do that with either pink or blue flowers. Some of the newer hybrids won't change color.
Reply:you are probably thinking of the hydrangea. it comes in pinks and blues