Edwin Lutyens, long-time gardening partner of Gertrude Jekyll, was a friend to both Sackville-West and Nicolson and a frequent visitor to Long Barn, and gave advice regarding Sissinghurst.
Sackville-West denied that Jekyll's work had an impact on her own designs, but Nigel Nicolson described Lutyens' influence as "pervasive".
Fleming and Gore go further, suggesting that the use of groupings of colours "followed Jekyll"; "a purple border, a cottage garden in red, orange and yellow, a walled garden pink [and] purple, a white garden, a herb garden".
Scott-James notes however that herbaceous borders, "Jekyll's speciality", were much disliked by Sackville-West.
Other influencers and friends were the noted plantswoman Norah Lindsay, the plant collector Collingwood Ingram, who was their neighbour at Benenden, and Reginald Cooper, one of Nicolson's closest friends, whose earlier garden at Cothay Manor in Somerset has been described as the "Sissinghurst of the West Country".
Sackville-West's considerable knowledge of old roses was deepened by her friendship with Edward Bunyard, plantsman, epicure, and the author of Old Garden Roses, who was a frequent visitor.
The historian Peter Davey places the garden at the very end of a tradition of Arts and Crafts gardening which by the 1930s, in the face of changes in "taste and economics", had almost come to its close.

The concept of "garden rooms" has been dated to the Romans, who included rooms within some homes that opened on one side onto a garden.
The horticultural scholar and gardener Marie-Luise Gothein identified such a room at Pliny's Villa Tusci, in her study A History of Garden Art.
In the late 19th century, reaction set in against both the Victorian fashion for elaborate bedding and Italianate formality, and the earlier 18th century landscape gardening modelled on the paintings of Claude Lorrain and Nicolas Poussin.
This led in part to a concept of the "garden room" (distinct from the architectural concept of a garden room) as a space out of doors, in which paths, corresponding to halls in a house, lead to enclosed gardens within the garden as a whole, conceived of as rooms.
The architect Hermann Muthesius described the style which developed into the Arts and Crafts approach in his Das englische Haus ("The English House"): "the garden is seen as a continuation of the rooms of the house, almost a series of ... outdoor rooms, each of which is self-contained".
A number of pre-Sissinghurst gardeners, including Jekyll and Lawrence Johnston, had designed in this style, and much of their work was known to Sackville-West and Nicolson.
This landscaping feature has since become an established one in garden design.

Many of the gardening themes developed at Sissinghurst were conceived during Sackville-West's and Nicolson's time at Long Barn: the prominence of roses, the emphasis on "rectilinear perspectives" through axial paths, and an informal, massed planting approach.
Jane Brown suggests that "without Long Barn there would have been no Sissinghurst."
Edwin Lutyens, long-time gardening partner of Gertrude Jekyll, was a friend to both Sackville-West and Nicolson and a frequent visitor to Long Barn, and gave advice regarding Sissinghurst. Sackville-West denied that Jekyll's work had an impact on her own designs, but Nigel Nicolson described Lutyens' influence as "pervasive". Fleming and Gore go further, suggesting that the use of groupings of colours "followed Jekyll"; "a purple border, a cottage garden in red, orange and yellow, a walled garden pink [and] purple, a white garden, a herb garden". Scott-James notes however that herbaceous borders, "Jekyll's speciality", were much disliked by Sackville-West. Other influencers and friends were the noted plantswoman Norah Lindsay, the plant collector Collingwood Ingram, who was their neighbour at Benenden, and Reginald Cooper, one of Nicolson's closest friends, whose earlier garden at Cothay Manor in Somerset has been described as the "Sissinghurst of the West Country". Sackville-West's considerable knowledge of old roses was deepened by her friendship with Edward Bunyard, plantsman, epicure, and the author of Old Garden Roses, who was a frequent visitor. The historian Peter Davey places the garden at the very end of a tradition of Arts and Crafts gardening which by the 1930s, in the face of changes in "taste and economics", had almost come to its close.
The concept of "garden rooms" has been dated to the Romans, who included rooms within some homes that opened on one side onto a garden. The horticultural scholar and gardener Marie-Luise Gothein identified such a room at Pliny's Villa Tusci, in her study A History of Garden Art. In the late 19th century, reaction set in against both the Victorian fashion for elaborate bedding and Italianate formality, and the earlier 18th century landscape gardening modelled on the paintings of Claude Lorrain and Nicolas Poussin. This led in part to a concept of the "garden room" (distinct from the architectural concept of a garden room) as a space out of doors, in which paths, corresponding to halls in a house, lead to enclosed gardens within the garden as a whole, conceived of as rooms. The architect Hermann Muthesius described the style which developed into the Arts and Crafts approach in his Das englische Haus ("The English House"): "the garden is seen as a continuation of the rooms of the house, almost a series of ... outdoor rooms, each of which is self-contained". A number of pre-Sissinghurst gardeners, including Jekyll and Lawrence Johnston, had designed in this style, and much of their work was known to Sackville-West and Nicolson. This landscaping feature has since become an established one in garden design.
Many of the gardening themes developed at Sissinghurst were conceived during Sackville-West's and Nicolson's time at Long Barn: the prominence of roses, the emphasis on "rectilinear perspectives" through axial paths, and an informal, massed planting approach. Jane Brown suggests that "without Long Barn there would have been no Sissinghurst."
Sissinghurst Castle Garden