The Orchid: Queen of Flowers
Orchids are the most diverse group of plants, with an estimated 30,000 different species and more than 200,000 registered hybrids. They are found in every habitat and every continent except Antarctica. They are unique flowers of incredible beauty, amazing diversity and intrigue.
The flowers have one highly modified petal called the lip or labellum that looks and functions radically different from the other petals. Some times it has a spur out the back and, in the extreme, the lip is shaped like a pouch!
Orchids are no longer the exclusive domain of the rich and famous. Orchid plants are now competitively priced against most house plants and most can be grown in New Zealand homes. “If you can grow house plants, you can grow orchids.” Like all plants they do have some preferences, one is not being grown in ordinary garden soil.
Growing orchids is now a popular hobby and there is likely an orchid society local to you where other people with a kindred interest meet and discuss aspects of orchid culture.
Growing Orchids in New Zealand
A number of orchid genera are grown around New Zealand and some of them are relatively easy for the average gardener to grow as long as the basics of air light and moisture are provided. Orchid roots require plenty of air and the plants are normally grown in a coarse bark mixture. This allows water to drain quickly. Like most plants, orchids require plenty of water while growing and a free-draining mix to ensure that their roots are not waterlogged. Orchids should be fed during their growing seasons with slow-release granules or liquid fertiliser at quarter to half strength.
As with any other plant, orchids manufacture food from sunlight so require good light, although most will not tolerate full sun. Positions which receive full sun can be tempered with shade cloth or filtering through trees.
Most orchids grown in New Zealand will grow without the need for heating. However, cool-growing does not mean cold-growing. Orchids do not like frosts and must be protected from them. Keeping them dry in the winter months will impart some cold tolerance. Some general tips follow. For a more thorough, season-by-season guide see our Cultural Notes page.
Cymbidiums are among the easiest orchids to grow and flower. They are cool-growing, meaning they can be grown outdoors in most parts of New Zealand. Flower spikes start to appear in the late summer to autumn, on the previous year’s growth. The flowers open in late winter to spring. Cut spikes last a long time in a vase and are an important export crop. Feed plants with a slow-release fertiliser in the spring and water well in the summer. Repot after flowering, ensuring not to over pot.
Australian native Dendrobiums are very popular. They are bred from a handful of species that are cool-growing plants. Most require a cool period in the autumn to initiate flower spikes. The flowers are followed by new shoots that mature over the summer and grow next year’s flowers. They can be naturalised in most northern gardens. Feed and water in the summer months and leave alone in the winter months.
Masdevallias have triangular flowers and come in some amazing colours often looking like shot silk. Each corner of the triangular flower extends out into a long thin strip giving it a most exotic shape. Masdevallias are cool-growing plants that appreciate more shade than other orchids. They need to be well watered, never allowing the plant to dry out, however excess water should be allowed to drain completely away. Fertilise at one-eighth strength once a month.
Known as the moth orchid this is an ideal indoor plant. It requires a warm bright spot, out of direct sunlight and cold draughts. On top of the fridge is a good growing place. The flowers are long lasting and it is possible to make the plant flower for many months by cutting off the spike just above a node once the flowers have faded. In time, a new branch will grow and produce more flowers. This can stress the plant and delay subsequent flowering. Phalaenopsis grow all year round and so must be regularly fed and watered. Never leave water in the axil of the leaves and avoid using slow-release fertiliser as it can burn the sensitive roots.
The Cattleya alliance includes Brassavola, Laelia and Sophronitis. The majority produce one or two leaves on the top of stout pseudobulbs that grow along a creeping rhizome. Flowers are produced from the top of new growths. Water in the warmer months and allow to dry out between waterings. Some heat in the winter is beneficial.
The Oncidium Alliance includes Odontoglossum, Brassia, Wilsonara and Miltonia. Most Odontoglossums flower in nine-month cycles and can be flowering most times of the year. They are cool-growing and must be kept cool and damp in the summertime. Oncidiums are more heat tolerant and a number of them require some heat in the wintertime.
Paphiopedilum orchids have a lip shaped like a pouch and are often called ‘slipper orchids’. The flowers can last for months on the plant. In the wild they grow in limestone country. Water well in the summer as they do not have pseudobulbs so should not be allowed to dry out completely. Most hybrids are cool-growing generally, but spotted-leaf plants require some heat.
If you have any questions or want to learn more, contact an orchid club near you.
Interesting Orchid Facts
New Zealand has about 150 species of orchids, of which only half a dozen live on trees (epiphytes) the rest are terrestrial. A number of them are only found in New Zealand and it is believed that a few others are natural immigrants from Australia.
The orchid Angraecum sesquipedale has a 300mm long spur where nectar is only found at the tip. Charles Darwin studied this orchid and predicted the existence of a moth with a tongue long enough to reach the nectar. Though initially ridiculed, 20 years later a hawk moth was discovered that possessed a tongue that long!
Size does not matter. The largest orchid in the world, Grammatophyllum speciosum, grows over 2.5m high and can weigh more than a tonne. Vanilla orchid vines can grow to 20m long. One of the smallest species, Bulbophyllum minutissimum, is only 3-4mm tall. Likewise Platystele jungermannioides has flowers that measure less than 0.5mm across.