Rhododendron Shamrock

Rhododendron Shamrock is a dwarf, compact and bright variety that doesn't go unnoticed in the garden in spring. From the month of March, this ericaceous bush is covered with trumpet-shaped, yellow-green flowers that are quite original. They contrast with a beautiful, glossy, evergreen olive green foliage. Despite its tropical appearance, the Rhododendron Shamrock is a very hardy small bush that can withstand strong frosts.

A hybrid of the Rhododendron keiskei, a Japanese bush with a very variable size ranging from 30 cm (12in) to 3m (10ft) in height, the 'Shamrock' variety reveals a very compact, naturally rounded and harmonious look. This dwarf bush forms a small, densely packed dome of approximately 60cm (24in) in height and width. Its branches bear beautiful evergreen foliage, composed of shiny, wavy, rounded olive-green leaves that are decorative all year round. The originality of the Rhododendron Shamrock also comes from the colour and earliness of its flowering, which appears as early as March and lasts until April, or even May. The flowers are rather small but extraordinarily numerous and completely cover the foliage. Shaped like trumpets, they display a unique pale green colour with hints of yellow. This bright flowering is ideal for brightening up shaded areas of the garden.

Remarkably hardy, the Rhododendron Shamrock can withstand temperatures as low as -20°. It is therefore suitable for regions with harsh winters, provided it is protected from excess humidity. In regions with hot and dry climates, it must be placed in a spot sheltered from the sun and receive regular watering in summer to avoid the root ball drying, which is difficult to recover from. The ideal location for the Rhododendron Shamrock is in partial shade, sheltered from the scorching sun. It thrives in acidic and moist soil.

Limestone soil would lead to leaf yellowing and the decline of the plant due to chlorosis. In open ground, in limestone areas, it is necessary to dig a hole at least 1 metre (3 feet) in diameter and 50 cm (20in) deep and isolate the location using a rot-proof material. This technique prevents the roots from coming into contact with the surrounding limestone soil. The rhododendron should not be planted deeply so that its collar is at the surface of the soil. Backfill with ericaceous soil, which can be supplemented with a mulch of leaves and decomposed manure. The shallow roots of rhododendrons require regular watering. The root ball must be kept moist at all times during the growing season, without being waterlogged. Pruning the rhododendron simply involves removing faded flowers at the end of flowering. This easy-to-grow bush is not particularly susceptible to diseases. However, it may be attacked by weevils that nibble on the edges of the leaves and rootlets without causing significant damage.

In open ground, the Rhododendron Shamrock will find a place in the foreground of a shaded bed, such as a woodland or north-facing exposure. Its size doesn't allow it to be planted as a standalone specimen but it will work wonders in a low hedge or as a border plant. Its small size also allows it to be grown in containers to adorn terraces, balconies, patios, and inner courtyards with its bright flowering and decorative foliage. It pairs perfectly with azaleas, camellias, and hydrangeas to flower in a shaded area for long months. It also works wonders alongside periwinkles or hostas for a successful foliage harmony.