Greenhouse of the Otaki Useful Plants Garden, former Otaki Herb Garden (大多喜有用植物苑 温室)

The Otaki site, in Isumi District, had housed the Otaki Herb Garden (大多喜ハーブガーデン) for about thirty years; it closed in 2024, according to the local newspaper Sotobo Keizai Shimbun. The press release of 19 February 2026 presents it as a cherished symbol of the region, reborn, while taking over its history, as the Otaki Useful Plants Garden (大多喜有用植物苑). The conversion is led by the horticultural company Universal Engei (ユニバーサル園芸社), of Osaka, and by its subsidiary Yoen (維苑), which produces the project and designs the garden; the interior architecture and furniture are by the TAAO office (會田倫久), the spatial direction by swarm. TAAO dates the completion of the works to April 2026. The first phase, which includes the greenhouse, the shop and the restaurant, opened on 20 February 2026; the outdoor garden and the other areas followed on 1 April. According to the office, the concept is a garden of useful plants of East and Southeast Asia, those that serve to feed, heal, clothe, heat, scent, build or please, which the place wants to bring back into daily life through a garden, a restaurant, a shop and a laboratory.

The TAAO office describes the starting point: an immense, ageing glasshouse built in a single piece, with a structure mixing heavy and light steel. To avoid complex strengthening works, the building was split where the structure changes: a wing A with a high-gabled frame, a wing B with a flat post-and-beam frame. Wing A was strengthened, closed again with new sashes at the cut, then air-conditioned as a greenhouse. Wing B lost its roof and its outer sashes down to the frame, and serves as an open-air garden, with louvred sunshades.

In the project's photographs, wing A is a glazed hall with large dark steel trusses, whose gable is visible from afar. The restaurant and the shop wrap around the greenhouse in an L, so that visitors can move from one to the other. Four lounging areas are set within the greenhouse: "under the eaves" beneath a bamboo roof, "in the ground" at a lower level, "on stilts" on a raised floor, and "on the veranda". Wing A thus remains, for the most part, the former glasshouse, with new sashes only at the cut.

The local press announces about 300 species from Okinawa and Southeast Asia in the greenhouse, according to the producer Satsuki Morita, who finds such a concentration of Japanese and Asian ornamental plants rare; the information on each plant was still in preparation in February 2026. The press release gives as its theme evergreen, useful Asian plants, in an indoor garden where visitors live a "special everyday" with them; the star tree is a banyan (ガジュマル) about 5 m tall. According to TAAO, these plants suit a temperature of 10 to 30 °C.

In wing B, turned back into an outdoor garden, the office places deciduous trees, flowering shrubs and trees with autumn foliage, as well as a vegetable plot. The restaurant serves a curry made with herbs grown on site and local game; the shop sells gardening items and herbal teas, and a perfume workshop, OHG Scent Research (有用植物調香室), works from the site's plants.

The greenhouse is the heart of a 6,000 m² site: visitors move between the plants, the restaurant and the shop, then on to the outdoor garden, open since 1 April 2026, whose appearance changes with the seasons. Dogs are admitted for a fee, but the site asks that they not walk in some areas of the greenhouse, where plants toxic to them grow.

From Tokyo, the JR Sotobō line leads to Mobara (about 90 minutes), then a Kominato Railway bus serves the "Odoro" stop in about thirty minutes; by car, allow about twenty minutes from the Ken-Ō Ichihara-Tsurumai interchange, with 120 free parking spaces. In winter the greenhouse stays mild while the area can see snow in January and February, according to the office.