Metrosideros – one of the genera in the extensive myrtle family ( Myrtaceae ). It includes about 50 species naturally growing on the islands of the Pacific Ocean from the Philippines to New Zealand, 1 species is found in South Africa. The greatest diversity is found in New Caledonia – 21 species, in New Zealand – 12, in Papua New Guinea – 4 species. It has been found that the seeds are easily spread from island to island by the wind. It remains a mystery how the 5 species of metrosideros reached Hawaii (possibly with strong high-altitude winds). These plants are often the first settlers on the cooled lava after volcanic eruptions.
All types of metrosideros are evergreens. They are very diverse in the type of growth – they are mainly shrubs, but there are large woody forms, many species grow like vines. Some species begin life as epiphytes, on the trunks of other plants. It was believed that epiphytic and semi-epiphytic species are plant stranglers, but this is not the case. They settle in the hollows of already dying plants and from a height they lower their aerial roots, reaching the ground. These species can also grow as terrestrial plants, forming a compact trunk. All species are characterized by flowers without petals, with reduced sepals and many long, brightly colored stamens. Flowers are collected in umbellate inflorescences, which are located at the ends of the shoots, less often in the axils, pollinated by birds and insects. Leaves are elliptical, oval,
Currently, some species have naturalized in Australia, Spain, the Sillou Islands off the southwest coast of Great Britain, Scotland, Hawaii, California, where they are used for outdoor gardening as flowering trees. In many countries, they are cultivated as tub and pot plants. Due to their plasticity and aggressiveness, some naturalized species are classified as invasive weeds. At the same time, in their homeland in New Zealand, metrosideros are under threat of a sharp decline due to being eaten by possums. They reproduce with fresh seeds, the germination of seeds drops sharply after a few weeks, especially if they are allowed to dry out.
Metrosideros received its scientific name from the English naturalist Joseph Banks for the strength of wood, from the ancient Greek word metra, which means “middle” and sideron – in translation “iron, iron tree”.
One of the most common and is known Metrosideros exelse, syn. M. tomentosa. It is one of 12 endemic species in New Zealand. Thanks to its vitality and beautiful flowers, it became the main tree of the Maori people, in whose language this tree is called Pohutukawa (Pouchekawa), which means “Splashes of the sea”. According to legend, the Maori is associated with it with the transition of the soul to another world. The tree was also widely used in medicine.
Tall metrosiders in nature usually grows as a large multi-stemmed tree and reaches a height of 25 m (hence the specific name), trunks and branches are entangled with aerial roots. It can begin life as an epiphyte, but more often it grows right on the ocean shore. Often the first to settle on recently erupted volcanoes.
Oblong, 6-8 cm long, dark green leathery leaves above have silvery pubescence below. The flowers, consisting of a mass of stamens, are collected in large corymbose inflorescences. The predominant color is red, there are dark pink and yellow (in the Aurea variety). Flowering peaks in December (summer in the Southern Hemisphere). Due to its flowering time, vibrant green foliage and spectacular red flowers, sublime are called the New Zealand Christmas tree. Currently, many varieties of this plant are cultivated, mainly selection is based on color and size of flowers. There is also the variegated cultivar Metrosideros exelsa Aureus, which has a golden strip along the edge of the green leaf.
Varieties, in general, are not bred artificially, but take natural mutations. It should be noted that with close growth, various species are capable of producing interspecific hybrids, which subsequently give rise to new varieties and reproduce in a vegetative way.
The powerful metrosideros ( Metrosideros robusta ), or North Rata, is also endemic to New Zealand. It grows into a huge tree 25 m high. Life begins as a semi-epiphyte, settling on other plants and sending aerial roots downward, entangling the host’s trunk, forming an often hollow trunk with a diameter of up to 4 m. It can grow on the ground, while forming a normal, but short trunk.
It is easily distinguishable from other species, has small, about 3-5 cm long and 1.5-2.5 cm wide leathery leaves with a pronounced notch at the end. The young growth has a reddish color, the leaves are covered with brownish hairs, which eventually disappear and remain only on the veins and at the base of the leaf. Inflorescences are very large, red. Flowering time November-January.
Umbellate metrosideros (Metrosideros umbellata), or South Rata, is the most common representative of the genus in New Zealand. It grows as a tree up to 15 m in height, rarely begins life as an epiphyte. Leaves are leathery, dark green, 3-6 cm long, strongly pointed. The flowers are composed of 2 cm long stamens collected together, mostly red in color, but white and yellow are found. Flowering in nature occurs in December-February. Very picky about soil moisture, it can grow on the coast, as it is resistant to wind and salt. It is a valuable melliferous plant.
We should also mention another endemic New Zealand view metrosideros Bartlett (Metrosideros bartlettii). It is on the verge of extinction; currently, there are only 34 mature trees in the wild. The species is characterized by white flowers, the tree reaches 30 m in height, starting life as a semi-epiphyte.
Metrosideros volatile (Metrosideros polymorpha) is endemic and the most common type for the six major islands of the Hawaiian Archipelago. In Hawaiian mythology, this tree is sacred, associated with the name of the goddess of fire and the volcano Pele. It fully justifies its name, from the ancient Greek polymorphos – diverse. It can grow in a wide range of climatic and soil conditions, from swamps to dry forests, and is one of the first to master frozen lava flows. Depending on the conditions, it can grow into a tree 20-25 meters high or into a spread-out shrub, the trunk can be even and slender, or twisted and grooved, the plant can give air roots that collect moisture and climb them like on stilts. Prefers moist forests with fertile, almost neutral soil.
The flowers are collected in inflorescences at the ends of the shoots and consist of many stamens, colored red, orange, salmon, yellow or pink. The flowers are woven into garlands (leis) and are used medicinally to relieve pain during childbirth. The plant is valued as a good honey plant. Durable wood is used in construction.
Home to the bush Metrosideros collina is an island near Australia (Marquesas Islands, Fiji, Vanuatu, etc.). There are two varieties of Metrosideros collina var . with ollina and M . collina var . villosa , which are described as separate species by some gardeners in the catalogs. Externally, M. holmovoy and M. changeable are very similar and for a long time were considered as subspecies of the same species. One of the cultivars M. collina is widespread Metrosideros Thomasii, characterized by its compactness, reaching a height of 2-4 m in nature. The flowers are orange, red.
Kermadec metrosideros (Metrosideros kermadecensis) , or Kermadec pouchekava, is a natural species from the Kermadec Islands. It grows in the form of a tree, reaching 15 m in height. Outwardly, it resembles M. sublime, but differs from it in smaller and more oval leaves and year-round flowering. M. Kermadek can easily hybridize with sublime metrosideros.
The Kermadec metrosideros has many variegated forms. Metrosideros kermadecensis Variegata is a cultivar with a golden edge and a green center. Variety M, opposite in color . kermadecensis Lewis Nicholls (Gala) – with a wide golden mean and a narrow green edge.
New Zealand is unique in that only grow here lianopodobnye kinds metrosideros – M. carminea , M. diffusa and M. perforata , M . fulgens , which, like ivy, emit short aerial roots and attach to tree trunks. So they reach sunlight, after which they bloom. We emphasize once again that these species are not parasites.
Carmine metrosideros (Metrosideros carminea) , or Crimson Rat, grows into a 10-15 meter liana. Prefers warm, humid forests, with some sun protection. Leaves are small, rounded, glossy, young shoots are red. The flowers are collected in inflorescences at the ends of the shoots, usually red in color. Blooms from late winter to mid-spring. The Carousel cultivar is a dwarf variegated groundcover.
Metrosideros sparkling , or climbing (Metrosideros fulgens syn. M. s candens) blooms, unlike many metrosideros, from late summer to early winter. The leaves are somewhat larger, and the trunks are thicker than those of M. carmine.
M. Tomasa (cultivar of M. Kholmovoy) comes to our flower market and sometimes variegated varieties of M. Kermadek are found. In room culture, they grow less than 1 m, rarely – up to 1.5 m.
M. Thomas grows as a compact dense bush, prefers bright sunlight, regular watering, although he can put up with a little drying. To increase humidity, regular spraying with water is required, but not on flowers. The soil pH range is from 3.5 to 8.5, but slightly acidic soils are optimal. Does not tolerate frost, minimum temperature +5 0 C.
In winter, in the absence of sufficient light to the plant necessary to arrange a rest period at +10 winter maintenance of C, moderate watering. For blooming in spring, exposure to the sun is required. Flowering time: spring-early summer. It lends itself well to formation, pruning is usually carried out at the end of summer. It is susceptible to damage by the scale insect, whitefly, sooty fungus, but in general, the plant is very hardy.