5 links
City Farmer's Urban Agriculture Notes
cityfarmer.org
A non-profit society that promotes urban food production and environmental conservation.
Gardeners Club
gardenersclub.co.uk
A directory of all local and national gardening related clubs, societies and organisations in the UK.
International Code of Nomenclature for Cultivated Plants
ishs.org
An extensive list of worldwide contacts of associations organised in taxonomic order.
The Garden Club of America
gcamerica.org
Umbrella organization for US and Canadian local garden clubs. Sites lists clubs and their websites, botanical gardens, pamphlets, and position papers.
The Mediterranean Garden Society
mediterraneangardensociety.org
International society for gardeners in mediterranean climates. History, membership information, journal contents, news, and event listing.