Use a piece of egg carton to anchor "bushes" in the garden.
Apply Mod Podge liberally so that the carton was very pliable, poke the stem into the carton piece, then shape it around the base mounded like dirt.
When dry, paint it brown and feather the base with black. The Mod Podge accomplishes two things: stiffening for shaping and gluing the material to the underlying base.
In this experience the egg carton could be used like paper mache skipping the layering of paper.