Living Blocks is an open-source recipe designed to produce blocks that can support plant and insect life. Using inspiration from the porous structure of rare limestone formations called tufa, Living Blocks uses waste fruit, vegetable and natural aggregates to produce a similar porous structure in a cement-based alternative. The project explores the ways in which we can build with nature to increase the biodiversity in cities whilst also developing our connection to nature. Through interviewing experts in ecology, conservation and art, I discovered that in order to increase biodiversity in cities we need to alter the way we build. Currently, cities are built with clean, smooth, regular shaped surfaces and spaces, with little focus on natural life. Living blocks aims to provide a basic open-source process people can use and adapt to build blocks or other shapes that provide complex, textured, bio-receptive surfaces that could provide rich ecosystems in urban spaces.