The hidden world of Australia's incredible orchids

By  Andrea Wild 27 November 2023 3 min read

The world of orchids is strange and alluring. Their flowers can be beautiful or cunning. Some species are popular pot plants, others are prized by hunters. Many are threatened by extinction before even being named by science.

In celebration of the new Flora of Australia Orchidaceae, an online encyclopaedia that lets you search all of Australia’s 1500 known orchid species, we’ve gathered some of our favourite facts about orchids.

We bake with orchids

Dr Bryan Lessard used to work with us describing and naming species of flies that were new to science. He now looks after Australia’s species lists at the Australian Biological Resources Study.

“Everyone knows I love flies, but orchids have a quirky, fun side,” Bryan said.

“Their name comes from the Greek word for testicle thanks to the shape of the roots of some orchids.

“We get the flavour vanilla from vanilla beans, which are actually the seed pods of the vanilla orchid. The flowers usually need to be pollinated by hand because the pollinators are only a few species of bee that live in Central and South America, where vanilla orchids come from.”

Orchids trick their pollinators

Potted orchids and cut orchid flowers are worth $2.5 billion per year worldwide. Their beautiful floral displays are designed to attract their pollinators. But around one third of orchid species deceive their pollinators.

Dr Heidi Zimmer, an orchid researcher at the Australian National Herbarium, said orchids have evolved complex deception strategies involving food and sex.

“Orchids are pollinated by various creatures, including birds, beetles, moths, flies, ants, bees and wasps,” Heidi said.

“Some orchid species offer food rewards but others only pretend to, often by mimicking the flowers of species that do offer food rewards. Orchids also use sexual deception, which involves pretending to be a desirable mate.”

One example is the Canberra spider orchid, Caladenia actensis. The orchid disguises its flower as a female thynnid wasp, both visually and using pheromones. This attracts male thynnid wasps, who attempt to carry the fake female away to mate with her. Instead, they pick up and transfer pollen between orchid flowers.

The end of this orchid’s species name gives a clue about where it lives. The suffix “-ensis” means the species was described from a certain location. In the case of Caladenia actensis, it's the Australian Capital Territory.

Naming new orchids supports conservation efforts

Orchids are one of the world’s largest families of flowering plants. Australia has more than 1500 named species and 90 per cent of them are not found anywhere else in the world.

“Many orchid species we don’t even know about yet are likely to already be threatened due to having small populations or living only in a single area," Heidi said.

“Giving a new species a scientific name and understanding where it lives is the first step to conserving that species. That’s why we’re so interested in naming new species.

“Our goal is for no Australian orchids to go extinct.”

There are 232 threatened orchid species in Australia. Last year we led a project to have 23 of them added to the International Union for Conservation of Nature Red List of Threatened Species, bringing the total to 51.

Flora of Australia bridges research and conservation

The new Flora of Australia Orchidaceae is a free digital resource covering all of Australia’s 1500 known orchid species.

“Flora of Australia Orchidaceae will be a great go-to resource for citizen scientists, researchers and conservationists alike,” Bryan said.

“People can find detailed information such as their appearance, flowering times and responses to bush fires.”

The Flora of Australia Orchidaceae was supported by the Australian Orchid Foundation and built by partners including the Australian National Herbarium, Australian Tropical Herbarium and Australian Biological Resources Study.