A Bit of Trivia

The あじさい or Hydrangea in English are big in Japan. In fact, by far the greatest species diversity is in eastern Asia, notably China, Korea, and Japan. I found out tonight from a Japanese quiz show that hydrangea flowers differ in colour according to the acidity of the soil! I never knew this! Apparently the flowers can be blue, red, pink, light purple, or dark purple and in these species the exact colour often mirrors the pH of the soil; acidic soils produce blue flowers, neutral soils produce very pale cream petals, and alkaline soils results in pink or purple. To get blue hydrangeas you modify the soil’s pH between 4.5 and 5.5. For pink to light red hydrangeas soil needs pH of 6.5 to 7.5. This can be done by adding ground limestone only around the plant to make the blossoms pink.