Chinese Azalea Rosata

The 'Rosata' Chinese Azalea, derived from Rhododendron viscosum, is a beautiful bush with relatively slow growth and deciduous foliage composed of small leaves of a bright green. This Azalea is particularly appreciated for its superb semi-late pink flowering, delicately scented. Very hardy, this bush will thrive in a gently sunny or semi-shaded position, in slightly moist acidic soil. It is an excellent choice for a small garden that it will enliven with its joyful flowering.

Azaleas are now classified as Rhododendrons, members of the Ericaceae family, which includes many ornamental genera (Kalmia, Leucothoe, Erica, Calluna, Oxydendrum, Gaultheria, Pieris...) as well as some small fruits (Vaccinium: blueberry, Arbutus: bearberry, Arctostaphyllos uva-ursi: bear grape). The Rhododendron genus is very rich in species (about a thousand). It includes evergreen and deciduous varieties, from miniature bushes to 15m (49ft 2in) tall trees. Their flowering covers almost the entire range of colours thanks to the numerous horticultural varieties available on the market.

Rhododendron viscosum is a species native to the eastern United States, where it is indigenous to a large geographical and climatic area, ranging from the cold New England (which explains its great hardiness down to -24°C (-11.2 °F), or even lower) to the subtropical Florida (which gives it one of its common names, Swamp Azalea). This amazing range is not its only peculiarity, as it blooms in June-July, which is very unusual, producing flowers with viscous tubes (hence its species name viscosum).

Rhododendron 'Rosata' is a horticultural hybrid obtained in 1938 by Batavus Bernardus Cornelis Felix, a breeder from the Netherlands. 'Rosata' is the result of a cross between the species, Rhododendron viscosum, with whitish flowers, and Koster's 'Brilliant Red', a variety of Azalea mollis (Rhododendron mollis) with orange-red flowers. This already old variety is still available on the market thanks to its ornamental qualities. It has even received a distinction from the highly renowned Royal Horticultural Society of England (an RHS Award of Garden Merit). It is a bush with relatively slow growth, growing only about 10-12cm (3.9-4.7in) per year. After 10 years of planting, it will reach approximately 1.40m (4ft 7in) in all directions, and can then grow slightly taller (1.80m (5ft 11in) high by 1.50m (4ft 11in) wide). Its deciduous leaves are quite small, about 5cm (2in) long, obovate (wider near the tip than at the base) and of a bright green. Its 4 to 5cm (1.6 to 2in) diameter flowers are grouped in clusters of 7 to 11 flowers, a pretty pink colour, with a darker central vein on each of the 5 petals. The reverse side of the petals is also darker, as are the flower buds before they bloom. All together, they create a joyful spring symphony in May and until June, succeeding the early flowering deciduous Azalea varieties.

In cool and dim climates, this Rhododendron can grow in the sun, but elsewhere, it is preferable to plant it in partial shade. It mainly fears drought and will appreciate cool and even moist soils, preferably acidic (pH 4.5 to 6) or neutral (by enriching the planting hole with heather soil), but definitely not alkaline.

The 'Rosata' Azalea will be ideal to celebrate the end of spring in a heather bed. You can create a romantic scene by associating it with white flowers, such as those of Kalmia latifolia 'Elf', a charming dwarf Mountain Laurel, whose narrow dark green foliage enhances the white corollas that bloom at the same time as 'Rosata''s pink clusters. To frame 'Rosata''s flowering, you will have plenty of choices among the countless varieties of Rhododendrons that flower before it, in April, and as you move towards summer, you will obviously have the abundance and generosity of Hydrangeas, with white, pink, red, purple, or blue flowers, often of large dimensions. But there is a much less known plant that deserves a place in your garden, behind 'Rosata', it is Oxydendron arboreum, or Sorrel Tree. This large bush indeed has it all: a long-lasting flowering in July-August, consisting of long clusters of small cream-white bells, and foliage that turns red and orange in autumn, rivaling with Witch Hazels and other champions of the genre!

Divided into 2 horticultural groups, the Rhododendron genus includes, on one hand, Azaleas, Chinese and Japanese, with small evergreen or deciduous leaves, equipped with 5 stamens per flower, and on the other hand, Rhododendrons, with ample, evergreen, and glossy leaves, whose flowers have more than 10 stamens. Although highly debatable from a botanical point of view, this classification is still widely used by horticulture professionals.