All Camellia x williamsii are hybrids between Camellia saluensis seedlings or cultivars and Camellia japonica or named C. japonica cultivars.
Meet the parents
There are thousands of forms of Camellia japonica I some have been in cultivation for hundreds of years and grown in Britain for about 300 years. Camellia japonica is a highly variable species ranging in natural habitat from the cold windy exposed cliffs of Northern Honshu or the coastal area of Southern Korea to the milder areas of Southern Japan. In addition C. japonica and its named cultivars have a wide diversity of flower forms and colours. The key contributions from C. japonica to C. x williamsii hybrids are cold tolerance and a range of flower forms and colours.
C. saluensis by contrast to C. japonica is a fairly recent introduction, seed of this species was notably introduced into Britain by the famous plant collector George Forrest on three expeditions to Western China in 1917-19, 1924 and 1925. Seed was distributed to the sponsors of the trip including Royal Botanic Gardens, Edinburgh and private land owners. These landowners included John Charles Williams at Carhays Castle in Cornwall, Col. Stephen Clarke at Borde Hill in Sussex, Edmund de Rothschild of Exbury in Hampshire and Col. George Johnson of Trewithen in Cornwall. C. saluensis in the wild varies in plant habit and flower size, colour (ranging from pale pink to deep pink and deep rose) and pollen colour (from white to buttercup yellow/orange) and size. They always have single flowers with 6 or 7 petals. In nature its habitat varies from deep shade under pine trees through semi shade to steep exposed slopes with little apparent nutrient or water available. It is not a very hardy species but Its key contribution to C. x williamsii hybrids are ability to produce an abundance of flowers over a prolonged period of time, under heavy shade, on poor mineral deficient soils which may verge on the alkaline.
J.C. Williams and the first hybrids produced at Caerhays Castle in Cornwall
At the start of the 20th Century, Camellias were generally considered to be tender conservatory plants only suited to larger landowners.
The first Camellia x williamsii hybrids produced around 1923 by J.C. Williams and his head gardener were to changed this view and encouraged subsequent hybridisers all around the world to attempt similar crosses. They combined key characteristics of hardiness, vigour and floiforousness. The first series of hybrids all had single flowers. They were crosses between seed raised Camellia. saluenensis; and Camellia japonica plants. The parents of the original C. x williamsii hybrids produced in Cornwall still survive against the walls of Caerhays Castle. Cultivars ‘J.C. Williams’, ‘St Ewe’, ‘November Pink’ and ‘Mary Christian’ were named and released after J.C. William’s death in 1940, they took a while to reach the nursery trade. Since the appearance of the first hybrids other varieties have been produced in Cornwall including some at Tregrehan garden near St Austell.
The ‘Donation’ story – From Borde Hill in Sussex
The landowners swapped plants among themselves grown from the seed that they received. Colonel Stephen Clarke hybridized a C. saluensis seedling obtained from J.C. Williams with a cultivar of C. japonica now called ‘Masayoshi’ (but known then as ‘Doncklaarii’) . C. japonica ‘Masayoshi’ has red flowers striped with white, the flower variagation is caused by a virus. Although it can set a few seeds it was used as a male parent because the C. saluensis set seeds readily. From a breeding point of view the plants flowered when young – even as one year old seedlings and therefore could be assessed rapidly. The outcome of this cross was C. x williamsii ‘Donation’ one of the first Williamsii hybrids introduced and still the most popular camellia in Britain. Jennifer Trehane relates the story of Col. George Johnson following a house guest who crept into the garden at Trewithen early one morning, only to see the guest stand in front of a plant of ‘Donation’ raise his hat and bow, before returning to the house.
Significant developments in flower forms in C. x williamsii
C. x williamsii hybrids have been produced internationally in Australia, New Zealand and America and the most significant developments since the war have arisen on the international scene. Among the significant raisers of new plants have been Professor Waterhouse in Australia from the 1950’s. But it was Les Jury from New Zealand whose breeding work carried out up to the 1960’s was a great step forward in the C. x williamsii story. He produced the first significant breakthrough in the production of peony, anemone, rose and formal double flower forms. Many are well-known varieties such as ‘Jury’s Yellow’. Les Jury’s plants were trialled in the 1960’s by Jennifer Trehane’s farther David Trehane, for suitability to cold condition. He also acted as his agent for their subsequent distribution in Europe. He carefully selected plants that flowered freely every year, with good blooms, “that held their heads up well” and drooped cleanly when finished. Also leaves that were not damaged in an average frosty winter were considered as an important criteria, non of Les Jury’s original selection of plants failed these tests.