Entelea arborescens aka New Zealand Mulberry

Entelea arborescens is an evergreen shrub or small tree from New Zealand. It belongs to the mallow family, Malvaceae. Older accounts placed it in the family Tiliaceae. Common names include New Zealand mulberry, corkwood, and New Zealand cork tree. Its native range includes both North Island and South Island. It grows in coastal and lowland forest, reaching about 41° south.

The plant reaches about 20 feet (6 metres) in height. It keeps its leaves throughout the year. Plants For A Future records flowering in May. Each flower has both male and female organs. The wood has an unusual practical value because of its low weight. It weighs about half as much as cork. People have used it to make floats and rafts. These uses help explain the common name corkwood.

Choose a sunny site with moist soil that drains well. This plant does not grow in shade. A loam with moderate fertility suits it well. It also accepts sandy soil and clay where drainage is good. It tolerates mildly acid, neutral, and mildly alkaline ground. Its evergreen growth can suit a sunny woodland edge. A position beside a south-facing or west-facing wall is another listed option.

Cold limits where gardeners can grow this species outdoors. Plants For A Future reports tolerance down to about 27°F (−3°C). In Britain, it generally needs a cool greenhouse. Outdoor growing is possible in the mildest parts of the country. At a Cornish trial site, potted plants suffered repeated frost damage. Frost killed their top growth despite cover from a polytunnel. Yet they grew back freely from the base. This shows that surviving frost need not mean keeping intact growth.

Sow seed in spring in a warm greenhouse at 68°F (20°C). Germination is reported as quick and straightforward. Keep seedlings under glass for at least their first two winters. Plant them outside in early summer, after the last expected frost. Give young plants winter protection for their first two years outdoors. Half-ripe cuttings taken in July or August also root readily. Plants For A Future lists no known food or medicinal uses. It also lists no known hazards, rather than confirmed safety for eating.