How the wider horticulture sector and Expos in general highlight the importance of the industry, the challenges and future opportunities.

Taking the Y position in the list of Expo Architects is Seattle-born Minoru Yamasaki, who made his breakthrough as an architect by designing the US Science Pavilion for World Expo 1962 in his home city.

This week, the A to Z of Expo Architects turns its focus to Greek-French composer, architect and director Iannis Xenakis, who created the revolutionary Philips Pavilion at World Expo 1958 in partnership with Le Corbusier.

Time capsules, those repositories of artifacts concealed for the future, have a long association with Expos. A project in Seattle this year is inviting people to continue a capsule tradition at the Space Needle on the site of World Expo 1962 - Seattle’s Century 21 Exposition.

Taking the W spot on the Expo Architects list is André Waterkeyn, a Belgian metallurgical engineer turned architect who teamed up with his brothers-in-law André and Jean Polak to design the centrepiece of World Expo 1958 Brussels: the Atomium.