In 2013, students at the University of Maribor in Slovenia designed a "green" 3D printer, known as PrintGREEN, whose output has the ability to grow grass. Conceived by Maja Petek, Tina Zidanek, Urka Skaza, Danica Renicnik and Simon Tran, they developed the device with the help of their mentor Duan Zidar. The innovative invention prints an earthy mixture in a variety of shapes and sizes, allowing you to express your gardening creativity with unconventional designs.
PrintGREEN, which is a specially-modified CNC machine, dispenses a combination of soil, seeds, and water, rather than plastic or metal. The mud holds its form and, over time, grass is able to grow from the organic, printed materials. There are a variety of uses for this type of machine, one of which is the application of single-surface compositions featuring lettering, artwork, and decorative patterns. In addition, PrintGREEN is capable of printing along the z-axis to produce bowls and other sculptural shapes. These objects don't contain seeds in their structures–instead, they incorporate a top-layer of grass to grow like a potted planter.