But a little felt will produce grass that appears to grow out of the soil.
Use scissors to cut the felt to fit your project. Use plaster, papier-mâché or insulation board (like Styrofoam) to create the shapes for the hills you will cover with grass. Apply a thick coat of water-based contact cement and press the felt into the still-wet cement. Let it dry. Wash your hands and the brush.
Sift on more soil as needed. You want the individual fibers of teased-up felt protruding through the soil, just like real grass. Trim excess with scissors.
When you’re satisfied with the scene, spray the area with a mixture of five parts water to one part Artist’s Matte Medium (available at art supply stores). Add a drop of detergent to the mixture to help soften the fluid so it doesn’t puddle as easily.
You’ll need to spray on enough of the mixture so the entire area has a white cast. It will turn the soil and felt a darker shade. Let it dry for about a week, and the original colors will return.