Introduction to the Ornamental Grass Garden: Ornamental grass is a general term for a class of herbaceous plants with beautiful shapes and rich colors, including Asteraceae, Lamiaceae, Gramineae, Liliaceae, Cyperaceae, Cannaceae, Verbenaceae, and Dragonite. Herbaceous plants belong to many families including Glossaceae, Araceae, Commelinaceae, and Onagaceae.