Last night at the sento, I was surprised to see what looked like leeks floating in the outdoor bath. Turns out it was shobu (ショウブ), commonly called sweet flag or acorus calamus. This sword-like plant represents samurais’ bravery, and is a traditional decoration for Boys’ Day (Tango no Sekku, 端午の節句) on May 5. It’s also medicinal.
Tokyo Green Space 