Grass is a common material found on many planets. It is a very important material, as it is used to make rubber, which is required in many crafting recipes, including hydroponics, which is a way to produce grass and other organics in locations where they are not. Can also be used to make Food and Cloth.
In-game description
"An organic substance found in terra and forest planets. Often green, but can be other colors. Useful for planting seeds for agriculture."