It was proposed to cut the sloping bank in front of the drawing room into a double terrace, a flower garden of some four acres would be placed to the east of the house, a kitchen garden of two acres to the west and an orchard of three acres to the north. Fourteen men were employed in thinning out the old trees and planting more valuable timber. Not less than 400 acres would be planted with trees. A Bowling Green would be laid out at the front of the house and new bridges would be built across the Tollie Burn and Alness River.

There were considerable alterations to the mansion in 1880/81, with Alexander Ross of Inverness as the architect. It was at this time that the Great Hall with its magnificent hammerbeam roof was built.

After the death of Sir Alexander in 1886, his son Kenneth inherited Ardross Castle, but by then Duncraig Castle had been greatly enhanced and he preferred life there. From 1887, Ardross Castle was tenanted by Sir J.H. Granville Smyth of Long Ashton, Clifton, and remained in his tenancy until 1898 when it ws sold to C. W. Dyson Perrins. It wasn’t long before he was making more alterations.

Charles William Dyson Perrins (1864-1958) was heir to the firm of Lea & Perrins, manufacturers of Worcester sauce. Described as a quiet, unassuming man, he nevertheless fulfilled many public duties in the area. He was a collector of pictures and other artefacts, many of which he gave to libraries and museums. Two servants in the castle were the poet Hugh Macdiarmid and his wife, and the former described Dyson Perrins in complimentary terms.