Plants can be defined as multicellular, photosynthetic organisms with reproductive structures that are more complex than single cells. By this definition, algae are not considered plants because they are either unicellular or their reproductive structures are essentially unicellular. Fungi, too, are excluded because they are not photosynthetic. At least 400 million years of diversification have resulted in a wide diversity of taxonomically distinct major groups of plants. Some of the most important groups of plants found in Virginia are described below.

Plants can be defined as multicellular photosynthetic organisms with reproductive structures that are more complex than single cells. By this definition, algae are not considered plants because they are either unicellular or their reproductive structures are essentially unicellular, and fungi, too, are excluded because they are not photosynthetic.