The work traces plant life from primitive origins through migrations and development, describes individual plant physiology and reproductive marriage systems, and surveys interspecies relationships such as allies and companions. It interprets aesthetic and musical qualities attributed to plants, considers scientific perspectives and reports on folklore, religion, and mythology surrounding them, and discusses mysticism and evidence for plant intelligence and higher life. Throughout, it argues for sympathetic observation, highlights human uses and stewardship, and urges ethical and respectful relations between people and the vegetal world.