The Prince of Wales was at the Kirstenbosch National Botanical Garden in Cape Town, South Africa, on Nov. 6 to meet his Earthshot Prize finalists

Prince William revealed another eco-friendly fashion choice as he took a stroll through the spectacular Kirstenbosch National Botanical Garden in South Africa on Nov. 6.

The Prince of Wales, 42, shared that he has a pair of sneakers that are made with materials from one of his Earthshot Prize finalists as he walked through the garden, which is nestled in the foothills of Table Mountain, Cape Town.

William was talking to Mary Allen from one of the shortlisted companies, Natural Fiber Welding, which makes plastic-free materials for use in shoes, bags and textiles. The prince met Allen and representatives from 14 other finalists who form the Earthshot Prize cohort this year.

“He said he’s got a pair!” Allen tells PEOPLE of the Purified sneakers that use the plant-based materials created by the Illinois-based company.

The prince’s eco-fashion choices have been capturing attention during his visit to South Africa, with the royal wearing several ties from the sustainable brand, Wilmok.

Later on Wednesday, five of the finalists will be awarded a $1.3 million prize each at a star-studded event, described by William’s team as his “Super Bowl moment.”

William has heard about their experiences over the last few days — mainly their involvement in the Earthshot Week’s Fellowship program, which helps them find solutions to grow and market their planet saving innovations.

William emerged in the sunshine walking with CEO of Earthshot, Hannah Jones, and was taken for a walk across the lawns. He was then shown around by Werner Voigt, Garden Director, and introduced to representatives from each finalist.

“It’s amazing just how much he deeply understands everyone’s solutions, which is testament to how passionate he is about this project,” Allen, who is the creative director of Natural Fiber Welding, tells PEOPLE. “He was really engaged and present. It is wonderful to have a conversation who is really present.”

“He was chatting with me a little bit about our regenerative supply chain work with smallholders in Thailand which is some of the biggest impact NFW can have. As a company committed to transitioning materials away from fossil fuels – something we need just as desperately as we need an energy transition away from fossil fuels.”