Metrosideros umbellata aka Southern Rata

Metrosideros umbellata, or southern rata, is an evergreen tree. It belongs to the myrtle family, Myrtaceae. Its native range includes New Zealand and the Antipodean Islands. It grows in forests and shrubland, from lowlands into mountains. Some plants also grow in the subalpine zone. Recorded habitats include the North, South, Stewart and Chatham Islands. The name Metrosideros lucida is a synonym.

The species can reach about 49 feet [15 metres] tall. Yet its size depends on the climate where it grows. In Britain, it remains a small shrub in suitable sites. It keeps its leaves throughout the year. Plants For A Future records flowering from July to August. Each flower has both male and female organs. Bees pollinate the flowers, and the plant attracts wildlife. The supplied species evidence gives no further flower or fruit details.

Choose a sunny site, as this tree cannot grow in shade. It needs moist soil that drains well but holds some water. Sandy, loamy and clay soils can all suit it. Lime-free soil is preferred, though plants tolerate some lime. Avoid shallow soil that lies over chalk. The listed soil range runs from mildly acid to mildly alkaline. Southern rata withstands exposed coastal sites and can form a hedge. It also suits the sunny edge of a woodland garden.

Cold limits its use outdoors in Britain. It succeeds there only in the mildest areas. Plants For A Future lists USDA hardiness zones 8–11. Raise seedlings in a warm greenhouse after sowing in spring. Cover the seed with only a thin layer of compost. Keep young plants under glass through at least their first winter. Plant them out after the last expected frost. Protect them from cold during their first winter outdoors. Half-ripe cuttings offer another way to raise plants.

Southern rata has value as an ornamental tree or hedge. Its tough, strong wood has served carpentry and shipbuilding. Plants For A Future records no known edible or medicinal uses. It also reports no known hazards, rather than confirmed safety. The source does not flag it as a weed. The supplied species evidence names no specific pests or diseases.