The World Flower Show 2014 is under way in the RDS, with as many as 20,000 people hoped to attend.
This is the first time Ireland has hosted the event.
The show is held every three years in one of the member countries of the World Association of Flower Arrangers. Previous host countries have included the US, Japan, UK, New Zealand and South Africa.
The organisers were successful in securing the bid against strong contenders from Barbados, Peru and Russia. Over the four days, 600 leading floral artists from all 31 member countries will compete.
Floral designer Jane Godshalk, faculty member of Longwood Gardens, a leading botanical gardens in the US, is one of the high-profile demonstrators.
Attractions will include lectures including Seamus O'Brien on Irish plantsman Augustine Henry, Prof George Sevastopulo on The Burren, and Dr Jennifer Goff on Eileen Gray.
The RDS Industries Hall is hosting a full selection of trade stands for Irish and international exhibitors ranging from floral art accessories and jewellery to Irish crafts and foods.