Culture

Discovering Hydrangeas and the Secrets of Their Hues

As Japan enters the rainy season, hydrangeas paint the country with their iconic blue and pink hues, gracing famous tourist spots and residential areas alike.

Published

6 days ago

June 15, 2024

Miruka Adachi

Hydrangeas in the rain on May 29 in Kita-ku, Osaka City. (©Sankei by Kotaro Hikono)

In Japan, every season brings its own marvel of nature. The flowers in vogue right now are hydrangeas — a genus of more than 70 species of flowering plants. They are celebrated for their ability to change color.

For city dwellers like me, the best part is that they add a splash of color to the most ordinary days. Whether next to a local pharmacy or a sidewalk in a residential area, I don't have to venture far to find them.

*Hydrangreas in a residential area in Setagaya-ku, Tokyo. (©JAPAN Forward by Susan Komori)*

Although hydrangeas grow in most neighborhoods, several tourist spots are renowned for them. For example, Kamakura is popular for its "hydrangea temples," including Hasedera, where the flowers line its famous pathways.

*Hydrangeas in the Hasedera Temple precincts in June 2023. (©JAPAN Forward by EH Kinmonth)*

The Science Behind the Color Change

Hydrangeas can shift from blue to pink and various shades in between. This transformation is primarily influenced by the pH level of the soil in which they are planted.

In acidic soil, hydrangeas tend to absorb more aluminum, leading to blue or purple flowers. The availability of aluminum ions in the soil is crucial for this color change. In alkaline soil, the lack of aluminum absorption allows the natural pink pigments to dominate. In neutral soil, hydrangeas often exhibit a mix of blue, pink, and purple hues, creating a variegated appearance that can be exceptionally beautiful.

*Hydrangeas in Ageo Maruyama Park in Saitama Prefecture. (©JAPAN Forward by Miruka Adachi)*

Cultural Significance

According to The Sankei Shimbun, hydrangeas were not particularly popular in classic Japanese literature. One reason for this was their color-changing characteristic, which was associated with fickleness and capriciousness.

In the Manyoshu, Otomo no Yakamochi uses hydrangeas to describe deception. Even in the Meiji era, poet Masaoka Shiki wrote, "Hydrangeas, yesterday's sincerity today's lie." Apparently, the image of hydrangeas only took a positive turn after World War II.

*Hydrangeas in Ginza, Tokyo on May 29. (©Sankei by Kanata Iwasaki)*

However, the flower appears to have held significance in folk beliefs. In certain areas of Kyoto, it was believed that hanging these flowers at the entrance of homes could ward off misfortune or attract wealth. Inspired by this folklore, some florists and flower arrangers recommend creating an asjisai mamori (hydrangea protective charm) by writing a wish on a piece of paper, tying it to the stems of the flowers, and hanging them upside down in the home.