Japanese Whisky Brewer Invents a Fake Soil for Rooftop Forests

In tightly-packed cities with a distinct lack of trees such as Tokyo, planting trees on the roofs of buildings is a common practice. In fact, every new medium-sized building in Tokyo is required to plant gardens on the roof. The problem? Soil is heavy and dense. The solution? Have a brewery invent a new fake soil, of course.

Yeah, since regular soil wasn’t really working out that well, Suntory, maker of whiskies, beers and many other fine beverages, developed a new synthetic called Pafcal that’s lighter and more solid. Less than half as much Pafcal than soil is needed to sustain plant growth, and a tree grown in the stuff can reduce the surrounding temperature by as much as 8 degrees Celcius. And with treeless cities increasingly suffering from the “heat island” problem with temperatures much higher than the surrounding areas, that’ll really make a difference. [Physorg]