The history of both public and private gardens in the United Kingdom is long one. Public benefactors such as Andrew Carnegie - he purchased and then donated Pittencrieff Park to the people of Dunfermline, Scotland - ensured that the ordinary working people could take their ease amongst a whelter of colourful blooms and shrubbery. Along with his establishment of many public libraries, this was genuine public philanthropy in the middle of the so-called Gilded Age.
Prior to the rise of the large scale public garden, huge areas of the countryside had formed estates for the nobility, and these had been landscaped according to their owner's wishes. Probably the most famous of all landscape architects was Lancelot 'Capability' Brown (1716 - 1783), who shaped more than 170 estates by creation of lakes, planting of trees and creating interesting vistas. The plantings were often protected from being grazed by cattle or sheep by the use of a 'ha-ha', a concealed trench with a gently sloping reverse wall, which meant that stock could not get at the 'landscape'. Horace Walpole, (son of British Prime Minister Sir Robert Walpole, and cousin of Horatio Nelson) was not overly impressed with Brown's work at Warwick Castle The castle is enchanting; the view pleased me more than I can express, the River Avon tumbles down a cascade at the foot of it. It is well laid out by one Brown who has set up on a few ideas of Kent and Mr. Southcote. Enclosed gardens were still used, however, close to the 'great house', though many were less formally laid out than they had been during Elizabethan times with their 'knot gardens' (there are also 'knot gardens' in the United States, including one at the Brooklyn Botanic Garden in New York).
The Castle Gardens at Warwick Castle in England are a semi-wild riot. Here we can see a profusion of rhododendron bushes, along with peonies, and there are roses and other flowering plants besides. The steeply sloping garden huddles underneath the curtain wall of the castle, and makes a bold splash of colour.
One of the most most amazing biological endeavors of the Victorian era, (other than skeleton hunts caused by 'dinosaur mania') was the way that botanists and plant collectors fanned out across the globe, seeking to bring back for learned societies and wealthy clients alike the most exotic plants and trees. Anyone who saw the State Nurseries of the Petite-Trianon, Versailles, France or the Royal Botanic Gardens in southwest London during this period could not fail to be amazed at the strange and beautiful plants brought back. At Kew, huge hothouses, supplied with steam heat, kept orchids and other tropical plants alive, so their blossoms could be admired by the many thousands of visitors.
Rhododendrons were brought to Britain by Victorian plant collectors. They are native to some Mediterranean countries and also Asia. Unfortunately, the introduction of one species, Rhododenron ponticum, has proved to be an ecological disaster. In my native Derbyshire, for example, large areas have been subject to invasive growth, and since there are no natural predators, and the plant is toxic to sheep, cattle and most insect life, it has to be physically dug out – a difficult task. Not only that, but the leaf and soil litter underneath the bushes (which can grow 20 feet high, or more) needs to be removed, as it remains toxic, and will contain seeds. All in all, the rhododendron (especially R. ponticum) was a bad choice, and it has done immense damage to the UK countryside.
Warwick Castle offers the best of both worlds; formal elegance created by Capability Brown outside the curtain wall, and in some areas inside, semi-wild riots of foliage and mounds of color. A magical place!