That Planters Neck is the peninsula portion of Annisquam, west of Lobster Cove, with convenient access to Mill River (which was impounded in the 17th century to provide the first water power for milling corn), the Annisquam River and Ipswich Bay? It was divided up into house lots by the early settlers, or planters. Copeland and Rogers write that: “One of the generally accepted stories about the early settlement of the Cape is that in 1631 a band of Pilgrims came across Massachusetts Bay and settled at Planters Neck, where they set up a fishing stage. The leader of that band is said to have been Abraham Robinson, and it also has been generally accepted that he was the son of Reverend John Robinson who had been pastor of the Pilgrims in Holland before they migrated to Plymouth.
This is a photo of the plaque at Planters Neck from 1930, acknowledging its tercentennial.
(edited excerpt from A Guide to The Maximus Poems of Charles Olson by George F. Butterick)