This volume serves as a comprehensive supplement to the foundational Dictionary of Gardening, addressing advancements in horticultural science and plant classification. Patrick M. Synge, a noted authority in the field, compiles updated botanical data and practical cultivation techniques to ensure the original encyclopaedia remains a relevant resource for serious gardeners and botanists. The text integrates taxonomic revisions and new species introductions to maintain the accuracy of the overarching reference work.

Experts recognize this supplement as a necessary update for those maintaining the complete Dictionary of Gardening series. Readers frequently note the technical density of the prose, which is intended for professional horticulturists and dedicated researchers.