Orchid Race To Save Underground Species

The Ghost Orchid: Inside the Race to Save Australia's Rarest Flower

Deep beneath the soil of Western Australia, a botanical enigma carries out its entire existence in darkness. Rhizanthella gardneri, the Western Australian underground orchid, is one of the planet's most mysterious plants. It lives, flowers, and sets seed without ever seeing the sun. Now, this subterranean marvel is critically endangered, sparking a desperate effort to rescue it from the brink of total extinction. A dedicated group of scientists is working against time to ensure this unique wonder of the natural world does not vanish forever.

A Childhood Fascination

The story of the orchid's modern conservation is deeply intertwined with the life of Professor Kingsley Dixon. As a child, his imagination was captured by a book about the native orchids in Western Australia, where he grew up. A specific drawing of Rhizanthella gardneri made a lasting impression. The concept of an orchid that lived underground, with a spectacular flower but no leaves or roots, was mesmerising. This early fascination planted a seed that would grow into a lifelong passion and a career dedicated to understanding and protecting this elusive plant.

The Young Plant Enthusiast

Describing himself as a young plant fanatic, Dixon dedicated countless hours to the Australian bush, which was the untamed scrubland close to his Perth residence. He collected native orchids, carefully cultivating them in a growing collection at home. When he turned thirteen, he had gathered an impressive selection of native orchids. Yet, the subterranean orchid, the plant from the centre of his favourite book, remained an unattainable dream. The closest he came during his youth was viewing a sample preserved inside a jar while on a unique birthday visit to a herbarium.

A Moment of Discovery

Years passed before the dream became a reality. In 1982, when he was 24, Dixon participated in fieldwork near the small community of Babakin in Western Australia. The team paused for a tea break. Venturing into the nearby bushland, he scuffed the soil with his foot. The simple action revealed the vibrant bracts belonging to the hidden flower beneath. It was a genuine eureka moment, the first time he had seen his lifelong obsession in its natural habitat. The chance discovery was a pivotal point, cementing his resolve to study the plant.

A Vanishing Marvel

Currently, Rhizanthella gardneri ranks among the planet's most uncommon orchids. The Australian government lists the species as critically endangered under its Environment Protection and Biodiversity Conservation Act. Habitat loss is the primary cause of its decline, with only a very small population of plants that continue to exist in nature. The population fluctuates yearly; in recent times, counts have plummeted to just three individuals, or on some occasions, zero sightings. The pressures of climate change add a further layer of threat to the species’ survival.

A Professor's Renewed Mission

This dramatic decline has given Dixon, now a distinguished botany professor at Western Australia’s University, a new and urgent purpose. Having transitioned from marvelling at the orchid's existence to witnessing its slide towards extinction, his focus has shifted entirely to conservation. Previously the director for the Kings Park and Botanic Garden in Perth, he is now spearheading efforts to rescue the subterranean orchid. His new dream is nothing less than securing its long-term survival for future generations.

Subterranean Secrets

The Western Australian underground orchid is not just rare; it is biologically unique. It is the single identified plant to finish its whole flowering process beneath the soil. Between May and July, it produces a captivating flower head containing as many as one hundred small, inward-facing, reddish-cream flowers. This "tulip-like" head is enclosed by large, fleshy bracts. A small opening at the soil surface, often hidden by leaf litter, allows pollinators, believed to be termites or fungus gnats, to enter. This hidden life makes it a profound evolutionary puzzle.

A Complex Alliance

The orchid's survival is entirely dependent on a complex three-way partnership. It has no chlorophyll and cannot photosynthesise its own food. Instead, it draws nutrients from a specific fungus, identified as a species of Ceratobasidium. This fungus simultaneously forms a beneficial relationship with the roots of a nearby shrub, the broom honeymyrtle (Melaleuca uncinata). The fungus acts as a bridge, funnelling carbohydrates and sustenance from the shrub over to the orchid, allowing it to thrive in perpetual darkness.

The Fungal Foundation

A mycorrhizal association is the scientific term for this type of beneficial bond with fungi, a relationship that is standard for orchids. Jacopo Calevo, a plant ecologist whose research covers orchids and climate shifts, explains these connections are vital. It is well known that orchid seeds are minuscule, like dust, and contain almost no nutrients to fuel germination. To sprout, they must connect with a compatible soil fungus which delivers essential energy for the embryo to grow. Without these fungal partners, the long-term existence of orchids would be impossible.

A Unique Dependency

For Rhizanthella gardneri, this reliance is considerably more complex and precarious. While most orchids form a direct relationship with one or more fungi, the subterranean orchid requires the fungus as well as the Melaleuca bush. This tripartite system makes it exceptionally vulnerable to environmental stress. Should any harm befall the host shrub—such as its death from drought or disease—the fungal bridge collapses. The orchid can no longer receive nutrients and is condemned to a slow starvation.

The Plight of the Wheatbelt

The orchid's fate is tied to its shrinking habitat in the Avon Wheatbelt area within Western Australia. This area has been extensively cleared for agriculture, leaving only small, disconnected patches of native bushland. These fragments are often surrounded by farmland, creating isolated islands of habitat. This fragmentation not only reduces the available territory for the orchid but also prevents it from migrating in response to environmental changes, trapping the remaining populations in increasingly hostile conditions.

A Climate on the Brink

Climate change poses a severe and escalating threat. Southwest Australia is a global biodiversity hotspot currently experiencing a significant drying and warming trend. Reduced rainfall and higher temperatures place immense stress on the entire ecosystem. The Melaleuca shrubs, the orchid's ultimate lifeline, are showing signs of stress, with many mature plants dying. Rising soil salinity, exacerbated by changing water tables, adds another layer of danger to the delicate habitat.

Adapting to the Heat

The orchids in Western Australia developed in a climate of extremes, building remarkable adaptations. Research by Jacopo Calevo, creating a model to project how temperature increases might affect them, indicates numerous species could probably endure direct warming. As an illustration, certain spider orchids can move their tubers deeper into the soil to reach cooler, more stable temperatures. However, while the orchids themselves may be resilient to heat, their essential fungal partners could be more sensitive, creating a critical weak link in their survival strategy.

The Wildfire Threat

Rising temperatures are not the sole danger related to the climate. More frequent and intense wildfires present a significant challenge for Australian orchids. Fire's effects are complex and vary between species. Research from 2025 into orchids from Western Australia showed that fire produced more victims than victors. Of the species examined, two-thirds were adversely impacted by blazes, while only one-third experienced benefits. This highlights how changes to natural fire patterns can dramatically reshape orchid communities.

Winners and Losers

The study revealed a spectrum of responses to fire. One clear beneficiary is Pyrorchis nigricans, often called the fire orchid, because it depends on the heat and smoke of a blaze to start flowering. In stark contrast, the blue sun orchid, Thelymitra macrophylla, was nearly wiped out entirely from scorched zones. These differing outcomes show that a "one-size-fits-all" approach to fire management in these habitats can have devastating consequences for more sensitive species.

A Fire's Aftermath

Calevo, along with his colleagues, investigated a 2022 fire's consequences on a known Rhizanthella habitat. The initial findings were alarming. A year following the fire, the fungi in the scorched earth were entirely different compared to untouched locations. The dominant fungi were types known for colonising newly cleared land, creating an environment not suitable for the subterranean orchid's growth. The essential Melaleuca shrubs had also been totally incinerated, severing the orchid's life support system.

Signs of Resilience

Remarkably, two years following the blaze, recovery signals were present. The population of fungi had begun to return to a state comparable to the unburnt habitats, demonstrating the soil's underlying resilience. The Melaleuca bushes were also resprouting from their bases. Research suggests that fire may even improve the long-term health of these shrubs. Since the orchid can lie inactive for multiple years, there is hope that as its partners recover, the orchid itself will eventually re-emerge.

A Dangerous Frequency

This natural resilience, however, has its limits. Calevo cautions that this rebound can only happen when fires occur with enough time in between for the ecosystem to heal. If wildfires become a more regular occurrence, the helpful fungi and their host shrubs lack sufficient time for regrowth. In that scenario, the dormant orchids would have no support system to return to, and local populations could be permanently wiped out. The timing and frequency of fire are therefore critical.

Image Credit - by Jean and Fred from Perth, Australia, CC BY 2.0, via Wikimedia Commons

The Perils of Control

Even planned burns, used within Australia for reducing fuel loads and preventing larger wildfires, can pose a threat. If these controlled fires are conducted when orchids are actively growing or about to flower, the plants may be forced to stay inactive to shield themselves from the heat. Another study reported that controlled blazes seemed to contribute to an additional drop in the threatened Queen of Sheba orchid's numbers, demonstrating the need for careful planning that considers the life cycles of vulnerable species.

Nowhere to Run

The combination of habitat destruction and climate change creates a calamitous situation. Globally, numerous plant species are reacting to warmer conditions by gradually shifting their ranges towards cooler climates. This is not a viable option for the subterranean orchid. As Kingsley Dixon points out, the surrounding landscape has been converted into farms, suburbs, and highways. There is nowhere left for this orchid to find refuge; its habitat is a shrinking island in a sea of development.

A Global Showcase

Raising public knowledge of the orchid's predicament is a crucial part of the conservation effort. During May of 2025, a dedicated exhibit was organized by Dixon, Calevo, and various orchid experts from across the globe for London's esteemed Chelsea Flower Show. It featured a photograph of the subterranean plant, leveraging its mystique to emphasize the critical need to safeguard threatened flora worldwide. Such initiatives bring the silent crisis facing flora like Rhizanthella to a worldwide audience, hoping to galvanise support for conservation action.

The Laboratory Ark

Alongside protecting its wild habitat, Dixon is pursuing a parallel strategy: cultivating the orchid within a laboratory. This project aims to create a captive, living collection that would serve as an insurance policy against it disappearing from nature. Recreating the orchid's complex world in a pot is a painstaking process, but it may be the last hope for securing the species' long-term future. This "ark" could one day be used to reintroduce plants back into protected, suitable habitats.

A Hard Lesson Learned

This is not the first attempt. During the 1990s, Dixon's team had managed to cultivate a living group of these orchids, along with their fungal partners and host shrubs. Tragically, that entire group perished near the year 2000 because of a straightforward mistake. An ambiguous watering rota over a Christmas holiday left the delicate plants to dry out. While frustrating, the loss felt less severe back then, since the number of plants in nature was thought to be a fairly robust 180.

The Urgency Grows

That sense of security has evaporated. Roughly four years ago, however, survey groups started reporting back from the orchid’s habitats with very worrying news. The population in nature seemed to have crashed, making the need for a backup collection critically urgent. With the orchid's numbers in nature plummeting, the pressure to succeed in the lab is immense. The lessons from the past now inform a renewed and more desperate effort to establish a stable captive population.

Rebuilding a World in a Pot

The method for cultivating the orchid is a delicate scientific operation. It follows the same procedure that proved successful during the 1990s. First, Melaleuca bushes are grown in pots. Next, samples of the specific mycorrhizal fungus, which have been stored, are carefully reanimated in a laboratory at Western Australia's University. Finally, the reanimated fungus along with valuable orchid seeds are placed on the host bush's roots, and the team can only hope that the intricate three-way relationship establishes itself once more.

A Passion Project

The complex lab work is not driven by a large, well-funded institution but by a small, dedicated group. The endeavour to cultivate the orchid in a controlled setting is led by Dixon himself, alongside what he calls a group of dedicated community volunteers. Their meticulous work, carefully piecing the fungus, bush, and seeds back together, is a testament to their dedication. It is a mission fuelled by a profound love for this unique plant, a passion that, for Dixon, stretches all the way back to his childhood.

A Hidden Family

Rhizanthella gardneri is not completely unique. The Rhizanthella genus contains a few other kinds of subterranean orchids found in other parts of Australia. These relatives, such as R. slateri and the more recently described R. johnstonii, also live subterranean lives, though some may break the surface slightly when flowering. The existence of this small family of hidden orchids highlights an extraordinary evolutionary path and underscores the ecological importance of Australia's unique environments. They all face similar threats from habitat loss and a changing climate.

The Future of a Ghost

The subterranean orchid of Western Australia is in a vulnerable position. Trapped in tiny fragments of a vanishing ecosystem, it faces the dual threats of habitat degradation and a rapidly changing climate. The fight to save it proceeds on two fronts: protecting the last remnants of its wild habitat and creating a protective population inside a laboratory. The fate of this botanical ghost, a flower that blooms without light, now depends on the dedication of a few determined individuals working to bring it back into the light of existence.