A plant or plants can represent many different things, including growth, development, evolution, refinement, production of good or useful things, life force, nature, God.
Also, pay attention to the plant and its context. A healthy plant might represent health or life force. A sick plant might represent an imbalance somewhere in your life. A plant can also represent a person, their life, or their quality of life.
Also, consider what the particular type of plant means to you. For instance, a palm tree might represent a warm climate or a vacation destination. A fern might represent a feeling of dampness and shadiness or darkness. A flowering plant or fruit tree might represent being productive or making useful things. A prickly cactus might represent a threat, obstacle, or irritable person.
If a particular part of the plant stands out, consider its individual meaning.