The Royal Horticultural Society
Britain's Gardening Charity, founded in 1804 to encourage the science, art, and practice of horticulture in all its branches.
http://www.rhs.org.uk/ - Detail
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The Royal Horticultural Society of Ireland
Member-led society dedicated to promoting the knowledge, skill, and practice of horticulture, arboriculture and floral art. Founded in 1816
http://www.rhsi.ie - Detail
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Royal New Zealand Institute of Horticulture
The mission of the RNZIH is to encourage, promote, and improve horticulture in New Zealand.
http://www.rnzih.org.nz/ - Detail
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