All About Orchids

New Zealand has more than 120 species of fascinating and diverse orchids. They’re usually not very showy, so you need to look carefully to find them in the wild. When you do spot one, please enjoy it without disturbing it, as many species are rare, and some are endangered.

Orchid Growth Habits

Orchids have two main types of growth habit; they can be either sympodial or monopodial. The types are derived from Latin - sympodial means “many-footed” and monopodial means “single foot”.

Most orchids are sympodial. This type grows out horizontally to form separate buds, that grow into distinctive thickened bulbous stems, each with their own root system (these stems are called pseudobulbs). Pseudobulbs store water and nutrients to help the plant tolerate periods of drought. Leaves and flowers then sprout from the top of the pseudobulbs.

Monopodial orchids grow vertically as a single upright stem, with leaves that keep forming from the growing tip as it gets taller. Monopodial orchids don’t form pseudobulbs (so they need to be monitored for watering more closely).

Orchids naturally form offshoots (known as “keikis”) that develop their own roots – these can be gently separated from the parent and planted out as new orchids. Sympodial types sprout kiekis from the base of their pseudobulbs. Monopodial orchids develop keikis at the base of the central stem, or from buds on the flower stems.

What Orchids Need to Thrive

Have you heard they’re temperamental and hard to grow? Well, some are…but most of them are pretty straightforward. The trick with orchids is simply to give them the conditions they prefer.

Light

Light is really important to get right. If indoors, a North facing window is the best bet, but watch out for direct afternoon sun during summer; it can burn leaves. Orchids will show you if they’re happy with the amount of light they’re getting: the leaves will be light green and pseudobulbs will be plump and rigid. If they aren’t getting enough light, leaves will be dark green and leggy, with soft, wrinkled pseudobulbs. If they are getting too much light the leaves will have a bronze or yellow-coloured tint to them, in extreme sun they’ll show obvious signs of burning.

The best way to grow perfect, pristine orchid specimens is to use artificial light, tailored to the species you’re growing.

Temperature

Most orchids prefer warm days and cool nights. Ideal conditions are where the nighttime temperatures drop substantially from the day’s high; cool nights actually promote flowering. Hardcore orchid lovers regularly open their windows or glasshouses at night to keep their orchids cool.

Humidity

Orchids natural habitats are often humid, so they respond well to moist air. They don’t like being constantly wet though, the moisture needs to be in the atmosphere, not on the plants.

It’s a great idea to group potted orchids close together, because it creates a little humid microclimate around them. You can also fill a plastic drip tray with large pebbles, part-fill with water and sit your plant on top of the pebbles to increase humidity around the plant. Mist spray the leaves a few times each week. In fact, you can even move your humidity-lovers into your bathroom if it gets enough light!

Water + Air

It’s important with orchids not to overdo the watering – moist is good, saturated is not. The majority of epiphytic orchids are adapted to moist but very free-draining environments, so they have evolved root structures that catch and hold water. These roots are covered with a spongy substance called velamen, that absorbs and retains water until it can be taken up by the plant. If the roots remain constantly saturated, they are at risk of rotting; because of this, good airflow is really important for orchids.

Good bark-based orchid potting mixes encourage aeration to the roots. Aerial roots that push out into mid-air help the orchid maintain a good ratio of moisture to airflow – they may look a bit ugly, but don’t be tempted to prune them off, or try to train them back into the pot!

Growing Medium

Orchids grow really well in pots (plastic or ceramic are best). The natural growth habit of the species determines the best way to plant them, plus the best growing medium to plant them into. Most orchids prefer a coarse bark mix for best drainage and aeration; Yates Thrive Orchid Potting Mix is ideal for the purpose.

Lithophytic species can be planted directly onto rocks or stone slabs, which makes them unique showstoppers in the garden. Orchids also look amazing in kokedama or hanging baskets, giving you extra options to place them in just the right spot.

Fertiliser

Yates Thrive Orchid Liquid Plant Food provides all types of orchids with the balanced nutrition they need. It gently feeds through both roots and leaves, while you are watering. Alternatively, Yates Thrive Plant Food Spikes for Orchids are really easy to use. Simply push the spike into the pot, then forget about feeding for for 2 months!

Types of Orchids

Cattleya

Cymbidium

Cymbidiums are an old favourite in New Zealand; those of us of a certain age will recognise the classic pistachio-coloured corsage orchid from their School Ball. A big reason for their enduring popularity is that they’re hardy and easy to grow; they’re well suited to NZ conditions. They’ve been bred in a scintillating range of colours and patterns, with winter and spring-blooming flower spikes lasting for many weeks on the plant. The distinctive flower spikes are tall and elegant; swollen-looking pseudobulbs are visible at the base of the long strappy leaves.

Popular cymbidium hybrids fall into two groups: standards and miniatures. Standards have larger flowers, about 8-12cm in width. Dainty miniature flowers can be as small as 2.5cm across.

Standard cymbidiums like very brightly lit locations but cool temperatures, up to 21°C and down to a minimum 10°C, so they’re best grown outdoors in NZ. Miniatures are a bit more forgiving, preferring moderate to bright light and temperatures between 10°C and 24°C, but they’re still better off outdoors or in a glasshouse. In temperate areas, it’s best to get them under cover (well protected from frost) during the cooler parts of the year.

Cymbidium leaves should be a light apple green. Deep green leaves may look lush but are usually an indication that the orchid is in too much shade for optimal flowering.

Cymbidiums like to be kept constantly moist, but it’s best to reduce watering during the winter months to avoid rot.

Because cymbidiums are often terrestrial in their natural habitats, they benefit from free-draining orchid-specific potting mix that contains bark or wood chips and composted bark fines.

Dendrobium

Dendrobiums are part of a huge genera, found naturally throughout Southeast Asia and Australasia. Because of the differing climatic extremes of their habitats, dendrobium species are very varied in their needs and care routines. They typically do best in daytime temperatures up to 30°C, down to a minimum 10°C.

Interesting species commonly cultivated in NZ are Dendrobium kingianum (Pink Rock Orchid), Dendrobium speciosum (Sydney Rock Orchid) and Dendrobium nobile (Noble Rock Orchid), all lithophytes that look superb planted on rocks, or in a hanging kokedama (wrapped with a rock in the middle, to prevent their roots from staying saturated). Popular hybrids include the fabulous local Dendrobium Pukekura.

It's fine to let them dry out between waterings.

Epidendrum

Oncidium (Dancing Ladies)

Paphiopedilum (Slipper Orchids)

Phalaenopsis (Moth Orchids)

Phalaenopsis orchids are epiphytes, native to forests in tropical Asia. They're often given as gifts, because they have stunning and long-lasting flowers that come in a wide range of gorgeous colours including pure white, pink, magenta, mauve and yellow. Despite looking like ethereal, mysterious divas, they’re an easy and rewarding plant to grow.

Because they only get filtered light in their natural habitats, Phalaenopsis thrive indoors in a spot with bright, indirect light. They do best in temperatures up to 24°C and down to a minimum 15°C, which is also a good fit with growing indoors. However, once it’s reliably warm, they often appreciate a spell outdoors in a lightly shaded spot.

Phalaenopsis don’t form pseudobulbs, so they like their roots to be kept moist and really benefit from high humidity; you can mist the leaves regularly. They prefer to live in an orchid-specific potting mix that retains moisture, but also allows aeration. They can be re-potted into bark-based orchid mix every three years or so.

Phalaenopsis can produce new shoots and buds from the stem that flowered last year, so just trim any dead sections from flowering shoots, don’t snip off the whole stem.

Vanda Orchids