Corynocarpus laevigatus aka Karaka

Corynocarpus laevigatus is an evergreen shrub or tree. It comes from New Zealand and belongs to the Corynocarpaceae family. Its common names include karaka and karaka nut. People also call it New Zealand laurel. It grows in coastal and lowland forests. Its native range reaches south to about 44° south latitude. Kew places it in the subtropical climate zone.

Wild trees reach about 33–49 feet [10–15 metres]. In gardens, plants often grow as bushes with spreading branches. RHS lists heights above 39 feet [12 metres]. It lists a spread of 13–26 feet [4–8 metres]. Plants take about 10–20 years to reach their full size. The dark green leaves are oval and feel like leather. They can reach about 0.66 feet [0.2 metres] in length. The plant keeps its leaves through winter.

Mature trees bloom from spring into summer. The small flowers range from greenish yellow to white. They form upright panicles, or branched flower clusters, above the leaves. Fleshy orange fruits follow, then ripen in autumn. Each fruit has a shape like an egg. The fruits add colour in season to this evergreen tree. RHS suggests it for coastal, informal, and subtropical gardens. It also suits pots on patios where conditions allow.

Grow karaka in rich soil that drains well but stays moist. It accepts sun or part shade and needs shelter. RHS says acid, neutral, and alkaline soils all suit it. Its UK hardiness rating is H2. This means it cannot stand freezing. PFAF lists USDA zones 7–10, at odds with that frost warning. In colder places, RHS suggests a frost-free greenhouse or conservatory. Use peat-free compost based on loam, and keep air flowing. Give plants indoors full light or bright, filtered light. Plants grown under glass may need pruning to curb their size.

Scale insects and glasshouse red spider mites may cause harm. RHS reports few problems with disease. It warns that eating the plant can poison people and pets. PFAF lists fruit flesh as edible. It also records seeds processed for food by past custom. Yet it warns that raw seeds are poisonous. Its accounts disagree on whether raw fruit is safe. These food records do not show that untreated fruit is safe. PFAF records that Māori used the trunk to make canoes. It also reports use of the plant to make insecticide.