Six countries from the Americas have confirmed participation in GREEN×EXPO 2027: the United States, Ecuador, Colombia, Bolivia, Panama and Haiti. This is based on the participation list published by the GREEN×EXPO Association (as of 9 September 2026) and the Ministry of Foreign Affairs list (as of 7 September 2026). Colombia was newly added in the 9 September 2026 list. Only the United States has gone on to sign an official participation contract with the Association.
GREEN×EXPO 2027 is the 2027 International Horticultural Expo. It will run from 19 March to 26 September 2027 at a site in Yokohama’s Seya and Asahi wards. The country details below come from the Ministry of Foreign Affairs’ basic data and the Association’s announcements, and are current as of September 2026.
North America
The United States
The United States signed its official participation contract with the GREEN×EXPO Association effective 14 January 2026 (announced on 6 February 2026). It was the first G7 country to sign. The United States Botanic Garden (USBG), which comes under the Architect of the Capitol, leads the exhibit with cooperation from the American Public Gardens Association (APGA). The theme is “The Pursuit of Happiness.” According to the Ministry of Foreign Affairs’ basic data, the US capital is Washington, D.C., its population is about 342.35 million (February 2026, US Census Bureau estimate) and its language is chiefly English. We also cover the United States in a dedicated article, currently available in Japanese only.
Central America and the Caribbean
Panama
Panama appears on the participation list, but as of September 2026 it has not signed an official participation contract and has not announced any exhibit information. According to the Ministry of Foreign Affairs’ basic data, its capital is Panama City, its population is about 4.51 million (2024, World Bank) and its language is Spanish. Japan is one of the Panama Canal’s principal users, and about 60% of Japanese-owned ships are registered under the Panamanian flag. In 2020 OECD/DAC statistics, Japan was Panama’s largest bilateral donor.
Haiti
Haiti is on the participation list too. As of September 2026 it has neither signed an official participation contract nor announced any exhibit information. The Ministry of Foreign Affairs’ basic data gives its capital as Port-au-Prince, its population as 11.58 million (2022, World Bank) and its languages as French and Haitian Creole (both official). Following the 2010 Haiti earthquake, Japan deployed Self-Defense Forces engineering units to the UN peacekeeping mission there from February 2010 to December 2012. Through March 2019, it also provided more than 320 million dollars in reconstruction and development support.
South America
Ecuador
Ecuador is on the participation list but, as of September 2026, has not signed an official participation contract or announced any exhibit information. The Ministry of Foreign Affairs’ basic data lists its capital as Quito, its population as 18.28 million (2025, World Bank) and its language as Spanish (along with Kichwa, Shuar and others).
Colombia
Colombia was newly added to the GREEN×EXPO Association’s participation list dated 9 September 2026. As of September 2026 it has not signed an official participation contract and has not announced any exhibit information. According to the Ministry of Foreign Affairs’ basic data, its capital is Bogotá, its population is 53.42 million (2025, World Bank) and its language is Spanish.
Bolivia
Bolivia is also at the announcement stage. As of September 2026 it has not signed an official participation contract, and no exhibit information has been announced. According to the Ministry of Foreign Affairs’ basic data, its capital is La Paz (Sucre is the constitutional capital), its population is 12.58 million (2025, World Bank) and its languages are Spanish along with 36 Indigenous languages centred on Quechua and Aymara. President Rodrigo Paz, who took office in November 2025, has pledged to improve relations with advanced economies.
Our take
Of the six countries from the Americas, only the United States has reached a signed contract. Given that the expo will be held on the former site of a US Navy facility, we think it is fitting that the US was the first to commit, and we expect its exhibit to focus on public gardens. The five Latin American countries all remain at the announcement stage, and Colombia was only just added in September. Panama and Haiti in particular have deep economic and cooperation ties with Japan, so we are curious whether they will go on to sign.
We will add any signing or exhibit news to the country notes above. For the other participating countries and organisations, see our participating countries guide. Dates, getting there, tickets and where to stay are on our GREEN×EXPO 2027 page.