Metrosideros excelsa Aurea

Metrosideros excelsa 'Aurea' is an evergreen bush native to New Zealand, suitable for the mildest climates. Its dense, dark green, slightly glossy foliage is adorned with a yellow edge that provides ornamental contrast throughout the seasons. Its flowering, which lasts a good part of the summer, makes it particularly attractive, as the scarlet red pompoms formed by numerous stamens emerge. Fairly easy to grow in slightly acidic soil and a sunny exposure in warm coastal areas, elsewhere it will need to be planted in a container to overwinter it away from frost.

Metrosideros is a member of the Myrtaceae family, which comprises 3000 species, with well-known genera such as Myrtle , Callistemon with bottlebrush-like flowers, and of course, the large group of Eucalyptus. There are 54 species of Metrosideros, trees, bushes, and woody vines, found in the Cape Province (South Africa), the Pacific Islands, and notably New Zealand, the home of Metrosideros excelsa. Originating from the coastal areas of the North Island, it has been introduced to the South Island. It naturally occurs in summer in the forests of Agathis australis - or Kauris - an Australian conifer, and sometimes even forms forests on its own. Known as "pohutukawa" by the Maoris, meaning "splashed by the sea," which aptly describes its resistance to spray (and wind). English speakers more commonly refer to it as the "Christmas tree" as it blooms at that time in this Southern Hemisphere country, where the seasons are reversed compared to Europe. In its natural habitat, the plant forms a large tree that can reach 20 m in height, with a trunk up to 2 m in diameter. The tree forms a broad crown, able to produce lateral branches that, upon contact with the ground, root to form new trunks. It also produces adventitious roots from the branches that hang down to the ground, giving it a very characteristic appearance. Lastly, its robust root system, well adapted to volcanic terrain, allows it to securely anchor into rock.
Metrosideros excelsa 'Aurea' is a horticultural variety with variegated yellow foliage ("aurea" in Latin), distinct from the yellow-flowered form of the botanical species (M. excelsa var. aurea). Much smaller in size than the species, this bush generally won't exceed 2.50 m in height with a spread of 1.50 to 1.80 m in warmer gardens; its hardiness is quite limited. It forms fairly dense vegetation, with a slow to medium growth rate, consisting of relatively flexible, thin branches. These branches bear opposite, elliptical to ovate, approximately 4-6 cm long, leathery, evergreen leaves with a glossy surface. Their dark green colour is brightened by a somewhat irregular yellow margin, giving them a superb appearance throughout the year.
From June onwards, the eye-catching inflorescences begin to appear. Typical of the Myrtaceae family, the flowers, mainly clustered in cymes at the ends of the branches, consist primarily of 4-5 cm long stamens, in a particularly decorative scarlet red hue. The 5 petals and 5 sepals are much more discreet and go unnoticed. The flowering period extends for several weeks, until August, or even a bit longer in some years. The ensuing fruits are small capsules with no ornamental value.

In the few areas mild enough to allow for its cultivation in open ground, Metrosideros excelsa 'Aurea' will blend beautifully in an exotic bed. Plant it alongside Proteaceae, such as the genus Leucadendron or Protea, whose irresistible patterns will complement your scene. Add another Myrtaceae with mauve flowers, such as Callistemon citrinus 'Mauve Mist' with long bottlebrush-like inflorescences, and to add height to your bed, a Brachychiton acerifolius. This lesser-known Australian tree will dazzle you with its resplendent scarlet red blossoms.