Just as each soul is unique, each plant is unique. In many cultures, it is believed that the life force (soul) of man is contained in the blood. Every cell of our body is nourished by our blood. According to the Old Testament (Leviticus 17:11):
כי נפש הבשר בדם הוא ואני נתתיו לכם על המזבח לכפר על נפשתיכם כי הדם הוא בנפש יכפר׃
For the life of the flesh is in the blood; and I have given it to you upon the altar to make atonement for your souls; for it is the blood that maketh atonement by reason of the life.
If the life force of man is contained in the blood, the unique personality and qualities of each person is reflected in the blood of the individual. Since the blood nourishes the cells in our body, every cell in the body becomes “ensouled”.
So too, the unique characteristics and qualities of each plant are reflected in the plant’s essential oils. This parallels with the human blood, and it is exactly this parallel which makes essential oils a unique tool of communication between the human soul and the plant soul (which carries the life force of the plant).