Every summer, Portugal's Azores islands, an archipelago in the mid-Atlantic Ocean, become awash in pillowy, colorful hydrangeas. The bushes, which bloom in shades of blue, pink, purple and white, have become a symbol for the region — and a hit on Instagram.
There are nine volcanic islands in the Azores spread over about 370 miles. One island, Faial Island, is also known as Blue Island because of the abundance of gorgeous hydrangeas that line the roads and accent the landscape.
The soil on this island is acidic with a pH value of 5.5 to 5.2, and it's high in aluminum — both of which make the flowers extra blue. (The pH scale goes from 0 to 14, with 7 being neutral. Acid soils have a pH of 6.5 or less, and alkaline soils are 7.5 or more. )
Hydrangeas that grow in less acidic soil with less aluminum content will bloom in shades of pink, purple or white. A single garden may produce bushes with multiple colors as the soil qualities can differ within even a small area.
There's a dark reason behind Faial Island's extra-fertile soil. A volcanic eruption in 1957 lasted 13 months, burying hundreds of homes and entire villages with lava and displacing thousands of residents. The lava oozed into the ocean and cooled, creating another mile or so of coast line and incredibly fertile soil.
Each of the towns holds some responsibility for taking care of the beautiful plants, whether pruning or planting. It's illegal to pick hydrangeas from public spaces like parks or the countryside. But if you live in the Azores, you probably don't need to pick them anyway. Nearly every property is adorned with at least one.
The Azores, with a population of about 250,000, are known for their nature attractions. Besides the beautiful blue hydrangeas, there are blue-green lakes, rolling green hills, and on the island of Terceira you'll find lilacs and other purple wildflowers in bloom. No wonder it's otherwise known as the Lilac Island.
While hydrangeas aren't native to the Azores, historians believe the plant arrived in the U.S. courtesy of immigrants from the Azores. In the mid-1900s, nearly a quarter of a million Azoreans (many of them fishermen) came to U.S. cities in Rhode Island and southeastern Massachusetts seeking better living conditions. Today, if you visit The Hamptons, Martha’s Vineyard or Nantucket you'll likely see stunning hydrangeas in the immaculate properties and gardens there.