Greenery Day (Midori no Hi)

What Is Greenery Day?

May 4th is "Greenery Day," a national holiday dedicated to "connecting with nature, appreciating its blessings, and nurturing a rich and open heart." The holiday was originally associated with April 29th, the birthday of Emperor Showa, who had a deep love of plants and nature. When April 29th became "Showa Day" in 2007, Greenery Day moved to May 4th — a date renowned for its lush early-summer foliage — and was upgraded from a simple "national holiday-in-between" day to an official holiday in its own right, adding a refreshing touch of green to Golden Week.

The History Behind the Holiday's Move

The name "Greenery Day" reflects Emperor Showa's deep knowledge of botany and his love for the natural world.

• The reasoning behind the move: From 1989 to 2006, Greenery Day was observed on April 29th. When "Showa Day" was created to commemorate the turbulent Showa era, the beautiful spirit of gratitude toward nature was preserved by transferring the name "Greenery Day" to May 4th — a date that had previously simply been a holiday sandwiched between other holidays.
• Emperor Showa, the botanist: Emperor Showa was, in fact, a researcher of international renown in the classification of plants and hydrozoans. His famous saying — "there is no such thing as a weed" — reflects a deep compassion for all living things, an idea at the very heart of this holiday.

The Science of Forest Bathing and Recovery

Spending time among greenery isn't just a pleasant diversion — it's a scientifically supported form of self-care.

• The power of phytoncides: Trees release volatile compounds called phytoncides, which have been shown to boost the activity of natural killer (NK) cells in the immune system and lower levels of the stress hormone cortisol. Forest bathing has also been medically shown to stabilize heart rate and lower blood pressure.
• The relaxing effect of green: The color green places relatively little strain on the retina, helping ease eye fatigue. The irregular natural patterns found in nature, known as "1/f fluctuations," can also guide the brain into a relaxed alpha-wave state.

Fun Facts About Greenery Day

• Free admission to national facilities: On Greenery Day, many national and public facilities — such as Shinjuku Gyoen National Garden, the Tokyo Sea Life Park, and the botanical garden affiliated with the National Museum of Nature and Science — open their doors free of charge, giving the public a chance to connect with nature and science.
• One of the most forested countries in the world: About 67% of Japan's land area is forest, putting it on par with countries like Finland and Sweden as one of the world's leading "forest nations." Few countries enjoy such an abundance of green space.
• An urban cooling effect: Through transpiration, the greenery of parks and tree-lined streets can lower the surrounding temperature by 1-2 degrees Celsius, making it an important tool for mitigating the urban heat island effect.
• Forests as "green dams": Forest soil absorbs rainwater and releases it slowly into rivers, helping to prevent floods and droughts and acting as a natural reservoir that supplies us with clean drinking water.
• The intelligence of plants: Modern botany has begun to uncover sophisticated networks — sometimes called the "Wood Wide Web" — through which plants exchange chemical signals and cooperate to defend themselves against threats.

Tips for Enjoying Greenery Day

• On Greenery Day, take a trip to a forest or large park. Step off the paved paths and listen to the sound of leaves rustling and feel the earth beneath your feet — a way to reset your senses after the hectic start of a new fiscal year.
• Bring some "new green" into your home — even a single small houseplant on a windowsill or balcony can provide a visually calming effect. Watching a plant grow day by day can bring a small but meaningful sense of nurturing into your life.
• Take a closer look at the nature right under your feet — wildflowers sprouting from cracks in the pavement, or new buds on street trees. Like the renowned botanist Tomitaro Makino, who found beauty in plants most people never notice, try updating how you see the world around you.
• Take one small action for the environment — using a reusable bag, picking up litter, or donating to a forest conservation organization. Turn your appreciation for nature's many gifts into a concrete act.

Let the Brilliance of Fresh Green Awaken Your Vitality

May 4th is a day to remember that we are part of a vast web of life. When you feel worn down amid the concrete and steel of the city, the sight of fresh green leaves catching the sunlight carries a simple, fundamental message: that mere existence has value. A month into the new fiscal year, have your shoulders been tense with stress? Today, take a cue from trees that grow toward the sky over centuries, and view yourself on a slower, more patient timescale. Step into nature's embrace, and you may find that your worries are just a single drop in the great cycle of the seasons. Take a deep breath and let a green breeze pass through you — that freshness is exactly what will help you shine after the holidays.