The Geographic Beds consist of six collections, each representing a different biogeographic region of the World:
- The Mediterranean Basin
- South Africa
- South America
- North America
- New Zealand
These beds are situated within the Walled Garden, adjacent to the original 17th century walls.
These provide a sheltered microclimate, allowing the cultivation of a number of borderline hardy species.
The beds highlight the diversity of these regions and the evolutionary adaptations of the plants in response to environmental pressures. Many of the plants found in the Mediterranean basin have highly scented, densely haired leaves containing essential oils. These features are an adaptation to drought stress, preventing excess loss of water from the plants during photosynthesis. A characteristic trait of plants from New Zealand is a growth form known as divarication, where the branches grow in a zig-zag fashion with much reduced leaves. This is thought to be an adaptation to prevent grazing of such plants by the now extinct native bird the Moa.
The Garden plans to develop these collections further, focusing on regions of the world known as Biodiversity Hotspots. Such areas hold high numbers of endemic plant species, yet face substantial threat to their natural vegetation. Over 50% of the world's plant species are contained within these hotspots which collectively cover only 2.3% of the Earth's land surface.