The BdS Handbook of Perennials provides detailed information on over 400 species. In addition to their origin and growth, it describes the morphological characteristics, site conditions, habitats, and sociability levels of the plants, as well as potential uses; a photo of each plant facilitates recognition and memorization. Furthermore, additional species and recommended varieties are mentioned. In the introductory part of the book, the authors discuss the habitats of perennials, illustrated with clear visuals. The appendix categorizes perennials according to these habitats, allowing for quick identification. The new edition, Perennials Handbook IIIa, focuses on important current perennials, grasses, and ferns, while aquatic and marsh plants are compiled in Handbook IIIb.