

Sugarcane is the latest ingredient in Allbirds footwear.
The sustainable start-up introduced its first flip-flop Wednesday made with SweetFoam, a proprietary outsole material derived from sugarcane and engineered with the world’s first carbon negative EVA.
The technology will be made available to the entire footwear industry.
Allbirds spent two years developing the sole material. Instead of petrochemicals, the carbon negative green-EVA is derived from renewable sugarcane, a “highly efficient crop” that grows with minimal fertilizer. The material is processed in facilities that are run entirely on renewable power.
“EVA is one of the most widely used components in footwear, and this is the first time since its inception that it has been made from a renewable resource,” Allbirds co-founder Joey Zwillinger said. “After years of research, we are proud to introduce this into our products, and to the industry in a broad and meaningful way.”
SweetFoam will be rolled out across Allbirds’ product portfolio. The company is also making the material available to the entire industry in an effort to “spur an industry sea-change and shift one of the dirtiest, and most widely used materials to be greener than ever before.”
SweetFoam is the second new material Allbirds added to its tight, eco-minded product range this year. The company introduced the Tree collection in March, its first non-wool footwear made with Tencel uppers.
“We’ve got a long way to go. This was never about just wool or just shoes. There’s a bigger thing at play, there’s a bigger problem to solve, and I feel like with the introduction of SweetFoam we’re really gaining momentum around that,” Tim Brown, Allbirds co-founder, added.

Allbirds launched the innovative material with Sugar Zeffers, its fourth product line and first flip-flop. The Japanese-inspired flip-flop provides a bouncy underfoot feeling with a contoured footbed and soft straps made with plant-based microsuede and recycled polyester. The straps are filled with cushy castor bean oil foam for added comfort.
The men’s and women’s Sugar Zeffers are available in limited edition charcoal, blue wave, limoncello yellow and mandarin orange. The $35 shoe—Allbirds’ cheapest model—is already sold out in some size and colorways online.
Customer have the opportunity to customize their flip-flops by purchasing additional interchangeable straps for $15 each.
On Wednesday, Allbirds also announced actor and environmental activist Leonardo DiCaprio and Andre Iguodala of the Golden State Warriors are new investors in the business. Warby Parker CEO Neil Blumenthal has also joined the company as a new board advisor.