The 2003 World Horticultural Exposition (in German: Internationale Gartenschau 2003) was organized in the City of Rostock in Germany.

The access roads to the newly built Warnow Tunnel, the new trade fair and congress centre, the integration of the historical ship type Frieden as a wharf museum, the reuse of the park after the exhibition and the improvement of infrastructure in Rostock were part of the project as well.

Thirty-two countries were represented with a national garden: Austria, Bolivia, Bulgaria, China, Colombia, Croatia, Finland, France, Greece, Germany, Hungary, India, Indonesia, Italy, Japan, Kenya, Latvia, Luxembourg, Mauritania, Netherlands, North Korea, Pakistan, Poland, Slovakia, Spain, South Africa, South Korea, Switzerland, Tanzania, Tunisia, United Arab Emirates, and Vietnam.

More than half of the visitors came from outside Mecklenburg-Vorpommern and one third stayed in Rostock overnight, resulting in 50 million euros extra sales in this region.

Despite this result the exposition closed with a deficit of 20 million euros due to lack of supervision by the authorities.

50 volunteers at the same time lived at a camp to knot and bundle the willow branches and set up the self-supporting construction.