One of the most exciting features of The Spheres are the living walls. With more than 25,000 plants woven into 4,000 square feet of mesh, these vertical gardens are an innovative demonstration of biodiversity.
Choosing the Plants
From afar, the walls offer a rich canvas of color, and up close, they boast more than 200 different species of continuous plant coverage. Like most of The Spheres’ plants, the living walls highlight flora from the world’s cloud forests, chosen for their ability to thrive in conditions that are comfortable for people.
Similar to natural cloud forests, the living walls demonstrate vertical stratification, which is the phenomena that certain plant species thrive at certain heights. In general, light at the base of forests is limited compared to the canopy. The same concept applies to humidity, temperature, and nutrient availability. In designing the wall’s plant palate, the horticulture team considered this. The base of the walls feature plants that prefer lower light levels, cooler temperatures, and more water—plants found here include many ferns, cool growing orchids, and aroids.
Highlights of the walls include a number of Phragmipedium orchids, which naturally grow on vertical surfaces in Central and South America.
Additionally, one of the walls features pitcher plants—carnivorous plants that have adapted to grow modified leaves filled with water and digestive enzymes. A few different species are represented, each exhibiting variation in trap morphology.