All plants heaven atman within as per Hinduism scriptures. The journey of an atman on mother earth starts by manifesting form of amoeba (single cell formation), the first formation in cosmic life cycle. It further evolves into multi-cell formation, then insect life followed by plant life.
Every single human being on mother earth, the atman within has already manifested every single type of plant life. The doctrine of liberation as detailed in Bhagavad Gita and Upanishads (independent spiritual treatises) is infallible.
It is true all human beings evolved from stage of amoeba, then evolving into insect life, plant life, animal life and finally the human form. From a cosmic angle all insects, plants and animals are our brethren. The atman within human beings liberates from cycle of birth and death only when human beings indulging in spirituality reached state of enlightenment.
Does this mean that human beings must stop eating plants for they had atman within! As per doctrine of evolution, the whole cosmic system is directly governed by laws of karma and evolution that acted simultaneously. Whether we eat a plant or not does not affect the journey of soul atman within. The plant shall keep evolving irrespective of what happens to the external form.