Beginning with an idea similar to a collaborative indoor garden, The Spheres were first envisioned as a single curved glass building filled with plants and tall trees. During early planning, the design team studied the form and function of several sphere-like conservatories around the world, including the UK’s Kew Gardens, the Mitchell Park Conservatory in Milwaukee, WI, and La Biosfera in Genoa, Italy. Eventually, three distinct buildings emerged, and their shape and geometry evolved over the course of the design process.

The very first plant logged in The Spheres plant collection was a Mountain Cacao specimen. Also known as Herrania balaensis, this Ecuadorean cacao species produces pods that can be used to make a sweet and high-quality chocolate.

One driving philosophy behind the plant collection was the concept that The Spheres should feel like “year five on day one.” In light of this principle, Amazon Horticulture sourced plants from botanical gardens, private growers, and universities all over the world years before The Spheres opened. These plants are still grown and cared for in the Amazon greenhouse as part of Horticulture's larger plant collection. Plants regularly circulate between The Spheres and the greenhouses dependent on the season.

June 2015 marked the start of construction of The Spheres. The Spheres are really two different buildings- an outer frame with an interior concrete core. The core was made with 12 million pounds of concrete reinforced by 2.5 million pounds of rebar. At the base of The Spheres, a 400,000-pound ring beam transfers the heavy loads of gravity, wind, and seismic forces from the glass-and-steel façade to columns in the floors below.

Not perfectly sphere, The Spheres’ steel frame is actually a geometric shape called the pentagonal hexecontahedron. The shape is based on one of 26 known subsets of Catalan solids named for the Belgian mathematician who first described them in 1865. The frame of the three Spheres consists of 180 elongated pentagonal modules. By connecting each angle of the module to a centralized hub, the architects created a fluid yet modular pattern that could be repeated throughout the building. A steel fabricator in Oregon mass-produced the modules that were shipped onsite and assembled like a puzzle.

The Spheres’ façade contains 2,643 panes of glass. The last pane was put into place in December 2016. Our plants need more daylight than the Seattle weather usually provides so the type of glass selected for the façade was important. The glass chosen is ultra-clear and energy-efficient, with a film interlayer to keep out infrared wavelengths that produce unwanted heat. To test it out, the Amazon Horticulture built a small greenhouse in Woodinville, WA using the glass planned for The Spheres. This mockup greenhouse allowed the team to test light levels, temperature, and humidity in a realistic environment.

The Spheres’ first plant resident was an Australian tree fern, Cyathea australis by name. Amazon Horticulture chose this particular specimen because it is one of their collection’s very first plants. It also was the first of many plant donations from our collaborative partners at the University of Washington botany greenhouse. The tree fern was first added to the collection in late 2014 and was grown and cared for at Horticulture's offsite greenhouse until its delivery to The Spheres on May 4, 2017. Today, this plant continues to thrive in the Fernery, the garden on the second floor of the 6^th Avenue sphere.

The Spheres’ largest resident, stands nearly 49 feet tall, 22 feet wide, and weighs nearly 36,000 pounds. Named for its scientific name, Ficus rubiginosa, "Rubi" was first planted in 1969 at the Berylwood Tree Farm in Somis, California. This species of tree was selected for a number or reasons—including size, aesthetics, and ability to thrive in the indoor environment that The Spheres provides. Before being planted in the 7^th Avenue sphere, Rubi made a 1,200-mile, cross-country journey to its final home. Because of the tree’s size, the top of the 7^th Avenue sphere was removed, and the tree was craned in through the top of the building.

With more than 25,000 plants woven into 4,000 square feet of wall, the Living Walls are an innovative demonstration of biodiversity. These walls are the brainchild of Horticulture Program Manager, Ben Eiben. Ben and his team assembled the living walls by growing the plants on mesh panels at the greenhouse. When the panels were ready, they were transported and attached to the growing surface. With careful preparation, the team assembled The Spheres’ tallest wall in only two weeks!

The Spheres celebrated its grand opening on January 30, 2018. They were dedicated by Amazon Founder and Executive Chairman Jeff Bezos, former Seattle Mayor Jenny Durkan, County Executive Dow Constantine, and Washington state Governor Jay Inslee, using an Alexa voice command as the ceremonial opening.

Since its opening, Amazonians, guests, and visitors have walked through The Spheres to take in the stunning flora and unique design. The Spheres stand as a recognizable landmark in South Lake Union, Seattle. On-staff horticulturists conduct visits daily to care for the plant life and envision further ways to innovate inside The Spheres. For an inside look with the horticulturists, follow them on Instagram and Facebook.