The Massachusetts Horticultural Society, sometimes abbreviated to MassHort, is an American horticultural society based in Massachusetts. It describes itself as the oldest formally organized horticultural institution in the United States. In its mission statement, the society dedicates itself to encouraging the science and practice of horticulture and developing the public's enjoyment, appreciation, and understanding of plants and the environment. As of 2014, it had some 5,000 members.