Manuka (Leptospermum scoparium) is New Zealand’s main pioneer shrub, and thrives after fire. Like bracken, it grows throughout the country, from the coast to the mountains, and tolerates wet or dry soils. It is extremely adaptable and hardy, and can flower and seed when just a few centimetres tall. Its woody capsules split open when dry or burnt, releasing thousands of fine light seeds that are spread by wind.
Germinating m?nuka seedlings need full sunlight to grow, as they have few food reserves in their tiny seed. They germinate prolifically – thousands to a square metre. These compete intensely for nutrients, water and light. Over time most m?nuka seedlings and saplings die, until just one tree dominates every few square metres.
Manuka is senile at 30–50 years, when it dies from insect and wind damage. As its canopy opens, other species germinate and grow, as it is too shady under the canopy for a second crop of Manuka.
Talking of Manuka
European settlers pronounced m?nuka in various ways. Some stressed the first syllable, some the second. In 1948, L. R. C. Macfarlane tried to sum it up: ‘North Islanders call this plant “marnaka”, South Islanders “manooka”, while the New Zealand farmers refer to it as a “bloody nuisance”.’ 1 The correct pronunciation is actually mahnooka.
1 L. R. C. Macfarlane, This New Zealand. Christchurch: Simpson & Williams, 1948, p. 39.