Hearne became a primary figure in the development of the English watercolour tradition. His work is defined by clear pen outlines and restrained washes of grey or yellow. Unlike many contemporaries who sought dramatic effects, Hearne focused on architectural accuracy and the quiet details of rural life. In works like Pristwick Church and Landscape with an Oak Tree, he used a methodical layering process to build form. He was also an early adopter of lithography, contributing to the Specimens of Polyautography collection.

Collectors value Hearne for his technical precision and his documentation of pre-industrial Britain. His prints offer a calm aesthetic that suits contemporary interiors. The muted colour palettes and architectural focus provide a sense of order and historical continuity. These works function as both artistic studies and historical records of the eighteenth-century British environment.