Located in Willunga, to the south of the McLaren Vale township, Edgehill Vineyard was established in the early 1970's by Peter and Anthea Bosworth. Willunga itself was settled in approximately 1837, and the Bosworths have been growing grapes in the district from the late 1840's.

Traditionally a region of mixed agriculture from the earliest Pioneer days, Willunga grew wheat, sheep, stone fruits and barley, as well as dairy cattle and almonds. Almonds were an important part of the local economy in the 1950's and 1960's, but Willunga was unable to compete with the South Australian Riverland region's unrestricted access to water for irrigation and cheap land for almond growing, and the industry fell into decline.

Many of the commercial almond groves became derelict as a result, and Edgehill Vineyard was established on one such property.

On taking up the reins at Edgehill in the mid 1990's, Joch Bosworth set about converting some 24 acres of Shiraz, Cabernet Sauvignon and Chardonnay (and a few rows of Viognier) to fully certified 'A 'Grade organic viticulture. Eschewing herbicides and insecticides, weeds are controlled by the use of the Soursob, a pretty yellow flower (considered a weed by many), used at Edgehill in the battle against other more damaging weeds. Featured on the label, and growing rapidly with the onset of winter rains, the Soursob (oxalis pes caprae) dies off in early spring as surface moisture dries, forming a natural weed mat which prevents the germination of other weeds.

By maintaining organic soil and biological activity and using preventative measures to deal with any pest problems, Joch and the humble Soursob have proven to be a very potent force in this viticultural Battle of Bosworth.