The Japan Government Garden is the largest single exhibit at GREEN×EXPO 2027, covering 2.5 hectares. Two ministries are behind it, the Ministry of Land, Infrastructure, Transport and Tourism (MLIT) and the Ministry of Agriculture, Forestry and Fisheries (MAFF), under the concept of “rethinking the Japanese view of nature and moving forward into the future”. The day-to-day running of the exhibit is handled by the 2027 International Horticultural Expo Association, the GREEN×EXPO Association. The site is a corner of the venue in Seya Ward, Yokohama, at the headwaters of the Izumi River, and it consists of a garden called Reiwa Nihon no Niwa (the Garden of Reiwa-Era Japan) and a raised-floor wooden exhibition hall split into east and west buildings.
The groundbreaking ceremony took place on 2 November 2025. The Garden’s own official website opened on 19 March 2026, and an outline of the exhibits was published on 22 May. Sponsorship has been open since 25 December 2025, and on 14 July 2026 recruitment began for the guide crew who will work in the Garden.
The groundbreaking on 2 November 2025: two ministers and the mayor turn the first sod
The ceremony ran from 13:00 to 14:00 on Sunday 2 November 2025, at the planned exhibit site inside the venue in Seya Ward. MLIT and MAFF organised it, with the 2027 International Horticultural Expo Association as co-organiser.
The organisers’ addresses came from Yasuyuki Kaneko, Minister of Land, Infrastructure, Transport and Tourism and minister in charge of the International Horticultural Expo, and Norikazu Suzuki, Minister of Agriculture, Forestry and Fisheries. Congratulatory speeches came from Takeharu Yamanaka, Mayor of Yokohama, and Kazuya Hashimoto, Vice Governor of Kanagawa Prefecture, and Yoshinobu Tsutsui, President of the GREEN×EXPO Association, spoke for the Association. The outline of the government exhibit was presented by Jutaro Minomo, chief director of the Japan Government Exhibit Promotion Council and professor emeritus at Tokyo University of Agriculture.
After an address by Prime Minister Sanae Takaichi, the first sod was turned by the Prime Minister, Minister Kaneko, Minister Suzuki, State Minister of Economy, Trade and Industry Ino, and Mayor Yamanaka. In her address, the Prime Minister announced that Crown Prince Akishino had taken up the post of Honorary President of GREEN×EXPO 2027. The ceremony also included a seed-sowing ceremony and a flower-arranging performance.
A landscape scholar leads it, and the three directors are garden and exhibition professionals
The chief director, Jutaro Minomo, is a landscape researcher whose fields are landscape architecture and environmental planning. He is professor emeritus at Tokyo University of Agriculture and holds a doctorate in agriculture. His past posts include professor and vice-president of that university, the first chairman of the Prefectural University of Kumamoto and president of the Park Foundation, and in 2019 he received the Uehara Keiji Award of the Japanese Institute of Landscape Architecture.
There are three directors. Toshihiro Inoue is senior managing director of Ueyoshi Zoen, a long-established garden firm in Kyoto, and has built gardens for shrines and temples, including the shrine-office garden at Fushimi Inari Taisha and the landscaping of the temple precincts at Gangoji, a World Heritage site. Shoichi Kiriyama is president of the exhibition planning company Bon Planning and also sat on the committee that reviewed the plan for the government exhibit at the 2027 Expo. Kiyohito Tamotsu is a director of LOSFEE and a registered landscape architect who has worked with the United Nations on greening deserts; he was producer of Japan’s outdoor exhibit at the Doha International Horticultural Expo in 2023 and 2024.
Japan’s first official participation in a world exposition was the Vienna World Exposition of 1873, and the Meiji government built a Japanese garden there. At Expo ‘90 in Osaka, the International Garden and Greenery Exposition, the government exhibit had two roles, a theme exhibit and a national exhibit of Japan, and the whole area of exhibition hall, garden and plaza was called the “Government Garden”. The basic plan for the 2027 exhibit looks back on that exhibit as having helped Japanese floral culture, including ikebana and bonsai, spread around the world.
Reiwa Nihon no Niwa, ikebana and bonsai
The garden at the heart of the exhibit is called Reiwa Nihon no Niwa. According to the official website, it takes its cue from the site at the headwaters of the Izumi River and the natural surroundings, building in green infrastructure such as water circulation and the recovery of local vegetation, and it draws on the culture and techniques of the traditional Japanese garden to arrive at an expression of the Reiwa era. The exhibition hall is a raised-floor wooden building in two wings, east and west, with earthen walls and other details chosen to fit the area.
Inside the hall, heads of the schools belonging to the Japan Ikebana Art Association plan to display one work at a time, drawn from six flower forms, with a different form for each period of the Expo. The cooperating schools named so far include Sogetsu, Ikenobo, Ryusei-ha and Ohara. The bonsai come from the Imperial Household Agency, which has cared for and passed them down at the Omichi Garden of the Imperial Palace; the plan is to change the display twice over the run. Among the trees the official site lists, a 390-year-old black pine named “Kashima” was also shown at the Japan World Exposition of 1970. A 340-year-old hinoki cypress was displayed at the Palace for the coming-of-age ceremony of Prince Hisahito, and this will be its first showing outside the Palace.
Exhibits that carry over materials and other legacies from Expo 2025 Osaka, Kansai can be found in several places around GREEN×EXPO 2027 (what carries over from Expo 2025). The Japan Government Garden is separate from those: it is a new exhibit built by the national government.
Sponsorship has been open since 25 December 2025
MLIT and MAFF have been seeking sponsors for the Japan Government Garden since 25 December 2025, with the 2027 International Horticultural Expo Association acting as secretariat. Sponsorship can take four forms: funding, donated goods, donated services and free loans of equipment. The items envisaged are outdoor heat countermeasures, equipment for the indoor exhibits, materials and equipment related to smart agriculture, and inquiry-based learning programmes, and the ministries say the list will be updated as planning for the Garden proceeds. Applications are received by the Japan Government Garden secretariat within the GREEN×EXPO Association, and the application forms are on the MLIT and MAFF websites.
An A1 horticultural expo, with a garden built by two ministries
GREEN×EXPO 2027 is not a general world exposition recognised directly by the Bureau International des Expositions (BIE) under the Convention Relating to International Exhibitions. It is an international horticultural exhibition of the highest class, A1, approved by the International Association of Horticultural Producers (AIPH) and then recognised by the BIE. The Japan Government Garden is being built by MLIT’s City Bureau, which is responsible for urban parks, and by the MAFF division that handles the flower industry.