Azalea mollis Gibraltar

Rhododendron Gibraltar, commonly called the Gibraltar Chinese Azalea, is a classic among the deciduous azaleas of the Exbury/Knap Hill group. Its spring flowering forms balls of rich orange flowers, finely crinkled and very visible in the garden. Ideal in acid soil beds, at the edge of woodland or in containers, this variety offers a subtle fragrance and good hardiness, proving to be very reliable in cultivation.

This plant belongs to the Ericaceae family. The cultivar ‘Gibraltar’, registered in 1947 in the line of Exbury hybrids created in England from Knap Hill selections, is sometimes marketed under the names Azalea (Exbury Group) ‘Gibraltar’ or Rhododendron (Azalea Group) ‘Gibraltar’, and is still sold under the horticultural name Azalea mollis ‘Gibraltar’. The Exbury hybrids combine the ancestry of Rhododendron japonicum (syn. R. molle subsp. japonicum) and other Asian and North American deciduous azaleas, sought after for their warm colours and hardiness.
The bush, of medium growth rate, adopts an upright to open, well-branched habit. At maturity, it reaches 1.20 to 1.50 m in height with a comparable spread. It will be limited to 0.80 to 1.20 m in a pot, depending on the container volume and maintenance. The deciduous foliage is formed of elliptical to lanceolate, 5 to 10 cm long, medium matte green leaves, taking on orange to reddish hues in autumn depending on exposure and soil. The young shoots are light brown and smooth, then become greyish with age. The flowering occurs from late May to June: these are terminal inflorescences in spherical umbels bearing 10 to 12 funnel-shaped flowers about 7 cm long; the curled petals open from brick-red buds into a deep orange enhanced by a yellow spot on the upper lobe. A light fragrance can be perceived at close range. The hardiness of this cultivar is rated at -20°C.

Plant ‘Gibraltar’ in the foreground of a large acidic soil bed or at the edge of woodland; morning sun will highlight its orange corollas. Near a pathway, one can better enjoy its subtle fragrance. Associate it with large rhododendrons, with ferns (Dryopteris, Athyrium) and hostas which weave a cool cover. To create a lasting spring scene, pair its warm tones with Chinese azaleas ‘Klondyke’ (coppery golden yellow), ‘Homebush’ (carmine pink pompons), ‘Persil’ (white with a yellow spot) or ‘Narcissiflora’ (pale yellow, fragrant double flowers). In a large container (at least 50 L), use ericaceous soil enriched with leaf compost, a thick mulch and water regularly with rainwater.

The Exbury azaleas were popularised by the Rothschild family in the Exbury Gardens (Hampshire), which still house many historic cultivars today, including ‘Gibraltar’.