The society was informally founded on September 19, 1840, when several local doctors and businessmen met in Worcester "for the purposes of mutual improvement in the theoretical and practical branches of Horticulture" and, in the subsequent weeks, organized an exhibition of fine specimens of orchard and garden plants from cultivators in Central Massachusetts.

[5] The group continued to host exhibitions annually and, by 1850, had a large enough membership and funds to purchase a plot of land and to construct its first formal headquarters, "Horticultural Hall", on Front Street in Worcester.

[7] In 1983, the board of trustees made a motion to found a botanical garden in Worcester County and, by the end of 1985, this was filled with the purchase of the Tower Hill Farm which is the society's main project and headquarters today.[when?

][8] Though the society moved from its Worcester headquarters in 1986, it remains active in the community, having spearheaded efforts in the Worcester Tree Initiative by providing more than 30,000 trees to replace those lost in efforts to eradicate the Asian long-horned beetle.

Trustees meet at regular intervals throughout the year, as well as on committees that support the staff of Tower Hill Botanic Garden.