- American Ivy Society - A non-profit organization dedicated to preserving the genus Hedera through education and promotion. Site offers contact information, species photos with descriptions, a classification system, care instructions, article collection, membership details, and a question answering resource.
- Hebe Society - International society based in Britain promoting the cultivation and conservation of hebes and other New Zealand native plants. Includes plant profiles and photos, FAQs, and links.
- New Ornamentals Society - Devoted to the study of new and rare ornamental landscape plants. Includes an online source guide and plant encyclopedia.
- Passiflora Society International - Dedicated to the preservation, study, and dissemination of Passiflora.
- Scottish National Sweet Pea Rose & Carnation Society - Society home page with Sweet Pea and Rose trial results, flower show venue and reports.
- The Geraniaceae Group - An international horticultural club interested in the species of all the genera of the Geraniaceae Family.
- The International Geranium Society - Society for the enjoyment of plants in the geraniaceae family centered in California. Events, information about membership and the magazine, culture tip sheets, and a photo gallery.
- African Violets@ (18)
- Camellias@ (13)
- Clematis@ (3)
- Clivia@ (3)
- Dahlias@ (13)
- Daylilies@ (68)
- Fuchsias@ (14)
- Hostas@ (29)
- Irises@ (35)
- Lilies@ (8)
- Orchids@ (122)
- Palms@ (8)
- Peonies@ (6)
- Primroses@ (3)
- Rhododendrons@ (17)
- Roses@ (119)
