John Claudius Loudon's Gardenesque approach to planting is generally misunderstood, even by the OED. His 1834 idea was that if planting designs are to be based on natural shapes, lines and forms then they MUST use exotic plants. If this is not done, the results may be beautiful and interesting but they will CANNOT be recognisable as works of art. In 1838 Loudon extended this idea by saying that the Principle of Recognition could also be satisfied by using formal geometry, by stopping plants from growing into each other and by uses grasses, rocks etc from outside the garden's locality. The designs influenced by of Loudon's ideas include Woodland Gardens, and the plant compositions of William Robinson, Gertrude Jekyll and Piet Oudolf. The Picturesque and Gardenesque phases of Loudon's work are the themes of Chapter 3 and Chapter 10 of Tom Turner's fictionalised dual biography of John Claudius Loudon and his cousin the Reverend Dr Claudius Buchanan. It is available from Amazon Kindle: https://www.amazon.com/dp/B0DJL69B9H