Perennials and Japanese pampas grass around a reflecting pond; hydrangeas and Hirado azaleas; an avenue of cherry trees and a meadow. The Day Osaka divides its grounds into five garden areas, each revealing a different expression of plant life as the seasons and the day’s light change. At this hotel on reclaimed land in Osaka Bay, the garden is not a backdrop that simply tidies the building’s exterior. It has become central to the stay, linking guestrooms, dining, and walks.
In the 10th Japan Tourism Awards announced on August 28, Castle Hotel Co., Ltd.’s “From an Artificial Island to a ‘Green Island’” was selected as one of 30 award-winning initiatives from 272 entries. The commemorative package that went on sale September 1 does not display that result as a framed honor or title. It translates the recognized garden into an experience guests can walk through themselves.
Guests Hear Why the Garden Was Cultivated
On the garden tour, staff guide guests around the property and share the history of its greenery and the thinking behind the garden. They also discuss plant characteristics and care, but the published information does not specify the tour’s duration, exact route, or which plants will be visible that day. Precisely because the garden changes with the seasons and the condition of its plants, prospective guests should confirm the latest details before booking.
Participants receive three benefits: an Instax photo taken in the garden, a small jar of local honey harvested on Maishima, and late checkout until noon. A photograph, the taste of the place, and an unhurried morning—each extends the sensory experience beyond the moment of seeing the garden. Guests may choose a room-only package or one that includes breakfast.
The Artificial Island’s Greenery Is Built from Layers of Care
The Ministry of the Environment’s published list of certified biodiversity-enhancement activities includes “Turning the Artificial Island of Maishima into a ‘Green Island’: The Nature-Positive Future Envisioned by The Day Osaka,” classified as a “maintenance” activity. The hotel states that it was certified as a Nationally Certified Sustainably Managed Natural Site in 2025. The recognition rests not on a one-time plan to add greenery, but on the continuing work of observing and sustaining an environment that has already grown.
According to the official announcement, the property monitors plants, wild birds, and insects with the Osaka Natural Environment Conservation Association and maintains a biotope mound that collects fallen leaves and returns them to the soil as leaf mold. Beautification activities carried out with local civic groups and high school students also support the garden. The flowers and trees guests see are the result not only of planting design, but of observation, leaf-litter cycles, and shared work with the community.
The hotel understands its garden through “five seasons”: spring, summer, fall, winter, and the threshold as one turns into the next. Its policy of limiting pesticide use and treating the dried forms of perennials as part of the garden’s change differs from decoration maintained in a constant color and shape. What remains on the day of a guest’s walk—and what is already moving toward the next season—also offers clues to the garden’s present state.
Five Gardens Draw Different Lines Through the Same Season
The hotel’s garden guide lists the Garden of Beginnings; the Hydrangea and Hirado Azalea Garden; the Garden of Sky, Wind, and Water; the Celebration Garden; and the Cherry Avenue and Meadow Garden. Around the reflecting pond, perennials and Japanese pampas grass lead toward log cabins. Elsewhere, hydrangeas, Hirado azaleas native to Japan, lilies, and perennials are combined. Even on the same grounds, leaf lines and plant heights shift between the water’s edge, meadow, and areas near buildings.
The hotel has not stated, however, that the tour visits all five gardens. The opening image is also not a photograph of the site; it was created from editorial elements—concrete, sea, planting, and the cycle of fallen leaves. The true point of entry is found between the guide’s words and the plants in motion that day. Rather than arriving to verify a pre-composed landscape, it feels more fitting here to ask why each place is cared for as it is.
Through December 31, the Garden Takes Center Stage in an Overnight Stay
The sales period runs through December 31, 2026. The official booking screen currently shows the room-only package, with check-in from 3:00 to 11:00 p.m. and checkout at noon. Because rates and availability vary by date, number of guests, and room, no fixed price is given. Current sales information, including the breakfast package, is available through the two booking channels identified by the hotel.
An award does not complete a garden. As the next leaves fall, grasses change height, and observation records are updated, the work of maintenance continues. What this package opens is time for guests not merely to consume a composed view, but to hear why that view endures. The hotel garden has moved one step closer from an amenity seen from a room to a purpose of the journey itself.