This large and splendid homestead was built for John and Edith Hammond between 1906-1908. They married in 1886, bringing together two early Pakeha settler families of the Rangitikei, the Hammonds of York Farm and the McKelvies of Flockhouse, Parewanui. The young couple settled at Merchiston (near present-day Rata), where they cleared the land and established a sheep, beef, and mixed cropping farm. In 1905 Edith received a legacy from her father's estate with which she decided to build a new and larger house. She commissioned Christchurch architect Joseph Clarkson Maddison to undertake the design of the house. At the time Maddison had just completed the design of the temporary show buildings for the New Zealand International Exhibition held in Christchurch.

Like many big country houses of the day, Merchiston was built to impress and to entertain, as well as to be a family home. The various Australian and New Zealand woods used in the house were the best available, and the very high standard of craftsmanship can be seen in the entrance hall, stairwell, and gallery. The 34-roomed mansion accommodated the family, servants and the numerous guests. The hall, dining room, and morning room were separated by sliding doors, which opened out into a ballroom, while the billiard room features the work of local Ngati Hauti craftsman. Today the house is surrounded by three hectares of mature gardens. In front of the house is an elaborate fountain, which was originally constructed for the New Zealand International Exhibition of 1906-1907. Local community groups have occasionally used the garden for charity events.

Merchiston Station Homestead, with its large size, highly-accomplished design and attractive setting, is one of New Zealand's more significant homesteads. It is also important for its connection with two settler families of the Rangitikei - the Hammonds and the McKelvies - and the architect J. C. Maddison.