The designed landscape associated with Newbiggin House was established in the first half of the 18th century by Sir John Clerk to the design of William Adair (The History of Gardening in Scotland). It incorporated many of the pastoral and poetical ideas held by Sir John for which he is renowned. The landscape was extended and informalised after the construction of the new Penicuik House in the 1760s. The structure, established by the mid-19th century, remains today.
The estate of Penicuik was acquired by John Clerk in 1646. His son inherited the estate, at that time called Newbiggin, on his father's death in 1674 and five years later he was created a Baronet of Nova Scotia by King Charles II. His son, John, was born in 1676; educated firstly in Scotland and later at Leyden University, Holland, he was a renowned scholar, politician, poet, musician and artist. In 1700, he was admitted to the Scottish Bar and after the Act of Union in 1707 he became one of five Barons at the Scottish Court of Exchequer. Sir John was a competent architect, working with William Adam in the early 1720s at his home at Mavisbank, Midlothian (q.v.), as well as designing additions for Drumlanrig, Dumfriesshire, the home of his friend the Duke of Queensberry. He was renowned for his ability to translate pastoral and poetical ideas into landscape design and planted extensively at Newbiggin in the early years of the 18th century and before his father's death, making him one of the pioneers of tree planting in Scotland. The house and designed landscape were improved in stages; their designs relied on the association and contrast of ideas and sensations to give a structure and sense of form. Hurley Cove and Pond were completed by Sir John in 1742. He felt the Pond was:-
"noteworthy for its position and solitude, which a poet only could describe. It is surrounded by hills and steep rocks, and no one can get access to it but by the mouth of a frightful cave. To those who enter, therefore, first occurs the memory of the cave of the Cuman Sibyl, for the ruinous aperture, blocked up with stones and briars, strikes the eye. Then there comes upon the wayfarers a shudder, as they stand in doubt whether they are coming among the living or the dead. As, indeed, certain discords set off give finish to musical cadences in such a way as to render the subsequent harmony grateful to the ear, so does the form of this mournful cave, with its long and shady path followed by the light and prospect, make the exit more delightful. For suddenly the darkness disappears, and as it were at the creation of a new world."
A summerhouse, now gone, was added on the edge of Hurley Pond:
"to entice my friends ... to walk for their diversion and in this I myself have found great advantage. The natural beauty of the place and the solitude which one finds here are a great help to the studies and meditation."
The structure of the designed landscape influenced by Sir John is indicated on Roy's map of c.1750. It shows three avenues converging on Newbiggin House, the square form of High Pond surrounded by woodland to the north-west and extensive woodlands along the south bank of the River North Esk. Sir John's son, James, was also educated at Leyden and had travelled extensively in Europe before returning to Scotland in 1750 to manage his father's business interests. He inherited the title of 3rd Baronet on his father's death in 1755. He too took a keen interest in architecture and was responsible for the construction of the new Penicuik House between 1761-69. Sir James died in 1782 and was succeeded by his brother Sir George, 4th Baronet. Sir John Clerk, 5th Baronet, succeeded just two years later and he held the estates until 1798 when the title passed to his nephew, the Right Hon. Sir George Clerk, 6th Baronet.
Sir George was a prominent Parliamentary figure and also an energetic farm improver who was responsible for reorganising the field pattern at Penicuik as well as the construction of new farm buildings. In his latter years, he commissioned enlargements to Penicuik House to the designs of David Bryce. Sir George died in 1867. He was succeeded by his son, Sir James, 7th Baronet, and three years later by his son, Sir George, 8th Baronet.
Sir George and his wife, Lady Aymee spent some of their time in London and, for a period at the end of the 19th century, Penicuik House was let. In 1899, whilst under the tenancy of Mr R.B. Rankin, an Edinburgh lawyer, fire spread through the house, totally destroying the interior. Lady Aymee was subsequently responsible for the conversion of the stables and offices into the dwelling that remains the family home today. She laid out the formal garden within the stable courtyard and the gardens adjacent to the north of the building. Sir George died in 1911 and was succeeded by his son. Sir John Clerk succeeded his father as 10th Baronet in 1943. He continues to manage the estate and is currently involved in promoting an appeal fund for the restoration of the house.