Until 1850, Whareroa was used for horticulture by Māori, who established their pā sites on the flat land.
The area was first farmed by Alexander MacKay in 1850 and it was later passed to the Wellington Hospital Board. In 942 Whareroa was acquired for defence purposes and became a training and recuperation camp for US Marines fighting in the Pacific campaign.
After World War II the Lands and Survey Department developed area as a public recreation and education farm park. When the department was re-structured in l987 to form Landcorp and DOC. Landcorp managed Whareroa and it was closed to the public.
Formed in 2003, the Whareroa Guardians evolved from a community campaign to prevent the farm being sold for private development. The community campaign to keep the land in public ownership was highly successful and in 2005, the Government purchased Whareroa to be managed by the Department of Conservation.
Whareroa Farm is now well established as a recreation reserve offering walking, picnicking, biking, and horse-riding, with links to the adjoining Akatarawa Forest and Queen Elizabeth Park across SH59. DOC, the Department of Conservation, works closely with the Whareroa Guardians Community Trust to manage the reserve. Native forest remnants, streams and wetland areas are being restored by volunteers led by the Whareroa Guardians.
Whareroa is a successful example of land being managed for conservation, recreation and farming.
It comprises regenerating retired pasture, pockets of native and non-native bush and a network of tracks, including the Camp Mackay Walkway.
Around 180ha of Whareroa Farm remains as a working sheep and cattle farm, which is not accessible to the public.