Are gardens natural? Are they art? Can they be both?
Gardens are only so because they are placed inside borders, separating us from the wilds beyond. Left alone, they will go back to their wild “natural” state. But we like organization, order, clean lines, no weeds, consistency of height and color–or at least a plan of each, where the tall plants go in the backs of the beds and colors are chosen according to fashion or color theory (thank you, Gertrude Jekyll). These things are what make us “ooh” and “aah” over gardens; even when they are designed to look “natural” they have been well thought out, planned to look accidental.
Does making a collection of plants conform to a planned design make them “unnatural”? If they are plants–and, thus, natural–then you can argue that a garden is natural if it contains plants no matter their form or shape or place of origin. In the eighteenth century, the landscape style of gardening was the height of fashion in England. The formal gardens at many large estates were torn up and replaced with gently rolling hills, trees and shrubs planted in clumps and drifts to mimic nature, serpentine lakes and canals, and specially created ruins and follies to attract the eye to far-off vistas. The landowners had nature re-created for their pleasure. It was still a garden, a collection of plants kept to a border–though a much more far-reaching one than before–and placed in a planned design. It was nature, it was “unnatural,” it was art. But it was still a garden.