|Botanical Name:||Coprosma robusta|
What does it look like?
Karamu is a shrub which grows to around five metres in height, with pale brown bark and sharp-pointed leathery leaves. The green flowers grow in dense heads and by autumn they turn into many small orange-coloured bitter fruit that attract birds. Karamu does not produce fruit until about three years after planting.
Where does it grow?
Karamu can be found as far north as Cape Reinga and as far south as North Otago or even Foveaux Strait, growing anywhere from sea level up to 1,200 metres. Often found where soil is poor or swampy or where conditions are windy or cold, it is a tough plant that will grow in difficult conditions. It tolerates full sun and shade equally well and is common in lowland and mountain forest. Karamu is wind hardy and frost tolerant when mature.
Seed Collection and propogation
After flowering in spring the berry like fruits develop first green and then to an orange colour. Each fruit is about 5-9mm long. Plants are quite simple to raise from seed if the seed is removed from the berry and soaked for 24 hours before sowing. There are two seeds per berry.
The seed can be sown fresh but in order to get an even distribution of seeds over the surface of the container it is a good idea to mix the seeds in river sand.
Growing tips … in your plant growing unit
Karamu doesn’t need to be potted on from the root trainers, but it is important to keep pruning it during late summer/autumn so it doesn’t get ‘leggy’ and spindly. Try to keep the plants to 30 cm height. Leggy plants do not grow as well as more compact forms when they are planted out, so regular trimming will help them establish.
Planting out for soil conservation
Karamu is one of the most useful plants for controlling soil erosion: it has been called the soil conservation workhorse. Karamu is suitable for general revegetation on bare infertile soils and provides good shelter for other more sensitive plants. A particularly hardy colonising species, it will grow well in moist or dry soils. Early growth is fast, so it provides good rapid shelter for other plants. Its dense, fibrous root system makes it good for stabilising soil.
Used to …
Maori made yellow dyes from a range of coprosma species, while children ate the fruit in spite of their rather bitter taste. Maori tohunga used branchlets of karamu in many religious and healing rites, including for ceremonies to lift the tapu from mother and child at childbirth and to ensure the success of the crop of kumara at planting time.
Did you know … ?
Karamu have both male and female plants which must grow near each other in order to produce berries and seeds. Worldwide there are over 90 species of Coprosma, of which 45 are found in New Zealand. Coprosma is in the Rubiaceae family which includes the beautiful gardenias and species that provide coffee and quinine, an anti-malarial substance.
Download Karamu information sheet
More interesting information about Coprosmas can be found on the Bushmans Friend website