What are the things to consider when planting Mānuka trees? Is Mānuka easy to grow? How long will it take for a Mānuka tree to grow from seed? We hope to answer your questions on growing Mānuka trees in this article.
The Mānuka, also known as kahikātoa (Leptospermum scoparium) is a special perennial and resilient plant. Sometimes, it is referred to as "tea-tree”, a name given to it by Captain Cook as they used the Mānuka leaves to make tea. Interestingly, they also brewed twigs from the Mānuka plant with rimu to make beer.
Mānuka/kahikātoa flowers have a very sweet smell. Their flowers are an important source of pollen and nectar for native bees, flies, moths and other insects. Mānuka flowers bloom in warmer seasons like summer and spring.
Early settlers in New Zealand used to struggle to clear their land of Mānuka trees as they were treated as invasive shrubs. Later on, however, significant research has been conducted about the Mānuka properties and benefits. Today, the Mānuka plant is considered a vital tool for rejuvenating New Zealand forests.
Where does it grow?
Mānuka/kahikātoa is common throughout New Zealand in lowland to low alpine areas up to 1800 m above sea level. It can be found in wetlands, river gravels and dry hillsides. It can even be found around active geothermal areas. The mature Mānuka tree is very tolerant of drought, strong winds and frost and it can grow at less fertile, colder, wetter and more acidic sites than the kānuka variety.
How to Grow Mānuka trees
Whilst the Mānuka is a hardy native plant, its seedlings are quite vulnerable to external factors like drought, weeds and animals.
| Stage | Growth Period | Details |
|---|---|---|
| Seed germination | 10 days to germinate from seed | Seeds are quite sensitive and an incorrect amount of fertiliser risks burning them. It is best to allow the seed to germinate in controlled conditions without fertiliser. |
| Germination to seedling | 3 months - From a baby to about 5 to 6 inches tall | Once the seedling is about 50mm tall, it’s safer to transfer the seedling to a PB2 bag and add slow-release fertilisers. It’s important to use high-quality potting mix. |
| Seedling to 2 ft plant | 6 to 8 months | Keep the plant well-watered. They love the sun. |
| Plant to tree | Mānuka trees can live up to 60 years. Typically, it grows from 2-5 meters but it can grow up to 15 meters in certain conditions. | Very hardy. Can tolerate harsh winds, drought. |
Extra care notes:
1. Some people plant the seedlings directly into the ground. However, the seedlings are susceptible to damage or competition for survival, especially against weeds.
2. Rabbits and deer sometimes eat the seedlings.
3. If you plant the seedlings directly to the ground, consider the location. They need to be well-watered, especially in the early stages (up to about 2 months or so).
4. In some cases, some plants develop black soot and die. The black soot is a fungus living on the excretion of a scale insect. It is these insects that suck the life out of the plant over a period of time. Spraying the plants with an insecticide would fix the problem. Even something like neem oil would help.
Mānuka’s benefits to the environment:
1. Their roots help prevent soil erosion.
2. Perfect nurse crops. Nurse crops foster the development of other plant species by creating shade and shelter from the harsh winds.
Mānuka benefits to the wider economy:
1. Mānuka honey is a well-known industry. The honey produced from the Mānuka plant is also claimed to have many useful properties.
2. In recent years, New Zealand annually exports a staggering amount of Mānuka-based products (in the hundreds of millions).
3. Planting and maintaining native plants or bushes such as the Mānuka on farmland improves land value. There are also innovative initiatives that promote leasing Mānuka farmlands for beekeeping.
4. In some cases, some plants develop black soot and die. The black soot is a fungus living on the excretion of a scale insect. It is these insects that suck the life out of the plant over a period of time. Spraying the plants with an insecticide would fix the problem. Even something like neem oil would help.
How can you help?
1. As much as possible, refrain from using Mānuka as firewood.
2. Spread awareness about the benefits of Mānuka.
3. Educate more people about how they can grow Mānuka trees on their land.
4. Let's plant more natives!
Mānuka seedlings are available at Awapuni nurseries in 2 great value options: Mānuka 25 Seedling Combo $30 - 25 Mānuka seedlings - 25 Slow-release fertiliser tablets - 25 PB2 Bags Mānuka 100 Seedling Combo $90 - 100 Mānuka seedlings - 100 Slow-release fertiliser tablets - 100 PB2 Bags
