I've already written briefly [
here] about the glorious hydrangea-covered seaside slopes in Brittany. Here's a photo of the German horticulturalist
Bernhard Meyer about to set off from Brittany in his truck loaded with freshly-cut hydrangeas:
My sister
Anne Skyvington, who admired these colorful fields when she visited us last year, has pointed out that the differing colors (blue, pink, mauve, etc) depend upon specific chemical elements that each hydrangea plant finds in the surrounding soil.
Click
here to visit the website (available in English) of a colorful nursery in another corner of Brittany.
The
degree of acidity of the soil influences the colors of many hydrangea varieties.
• In a strictly neutral soil (pH 7), varieties of plants that are naturally reddish will produce either pink or crimson flowers, whereas bluish varieties will turn mauve.
• Varieties of plants that are naturally bluish will express themselves most vividly in a slightly acidic soil (pH between 4.5 and 6.5).
Apparently changing the colors is easier said than done, and gardeners might need to experiment, and maybe use a dose of chemicals containing aluminium.
To be honest, I must admit that I failed dismally in my early attempts to introduce hydrangeas in the alkaline limestone soils of Gamone (pH often greater than 8.5). As everybody knows, if Brittany is indeed Brittany, it's for sound scientific reasons.