Unveiling the Rare Plants of Kauai

The lavish landscapes of Kauai are known for its rich biodiversity, let’s be captivated by the rare plants of Kauai. The paradise of Kauai is home to a hidden treasure trove that few have been fortunate enough to witness. These botanical wonders have captivated the hearts of scientists and nature enthusiasts alike, drawing them into a world of biodiversity and the sacred ecosystem of Kauai. As you wander through the dense forests and vibrant gardens, you’ll discover why Kauai is also known as the “Garden Isle,”. The island’s isolation has allowed these rare plants to evolve independently over centuries, resulting in a array of flora found nowhere else on Earth. The magnificent beauty of Kauai’s rare plants lets us express our heartfelt gratitude for the immense beauty that surrounds us. As we venture deeper into the heart of Kauai’s verdant rainforests, we are greeted by towering trees, vibrant flowers, and verdant ferns emerge from every corner, painting a picture of natural grandeur. However, our search lies beyond the common sights as we are on the pursuit for the rarest of the rare. Our excitement and anticipation are profound as we navigate the dense rainforests, treading carefully to protect the delicate ecosystem that harbors these precious botanical treasures. After days of arduous trekking, the botanists stumble upon a secluded clearing, bathed in dappled sunlight. Our eyes widen in awe as we lay gaze upon a sight that is nothing short of miraculous—a cluster of rare plants, resplendent in their vibrant hues and intricate forms. Each plant seems to possess a story of its own, a testament to the resilience and adaptability of nature. Cyanea Kuhihewa, this beautiful plant is endemic to Kauai, meaning it is found nowhere else on earth. Sadly, it is also one of the rarest plants in Hawaii, with only a handful of individual bunches remaining in the wild. Cyanea kuhihewa is a Hawaiian plant thought to be extinct but recently rediscovered. Oceanic island plants are uniquely adapted to their environment. Globally, many island species are now threatened needing extensive conservation management to survive. We highlight this global conservation challenge and provide an example from Hawai’i of how we may safeguard critically endangered species from extinction. Our second exploration takes us deeper into the rainforests of Kauai, where a symphony of vibrant colors and fascinating shapes awaits. Here, we found the elusive Kauai Hibiscus, a flower so exquisite that it seems to have been painted by the hands of a master artist. Its vivid petals, ranging from deep buttery to delicate orange, create a mesmerizing spectacle that leaves us feeling grateful for the colors of nature. The Hibiscus, kokio subsp. saintjohnianus (in Hawaiian: Kokio; Kokio Ula; Kokio Ulaula; Maku) is a well-known and popular flower, prized for its vibrant colors and beautiful blooms. However, the hibiscus that grows on Kauai is a bit different from other varieties. These plants are hybridized, meaning they have been crossbred with another variety of hibiscus to create a new color or type. For example, the Kula hibiscus is a cross between the red hibiscus and the white hibiscus, resulting in a pink flower. Kauai’s climate is ideal for growing hibiscuses, and as a result, these hybrid plants are some of the most vibrant and beautiful in the world. If you’re ever lucky enough to visit Kauai, be sure to take some time to admire these stunning flowers.
Laukahi (Plantago princeps var. anomala) is a small erect or ascending woody shrub that grows on steep slopes and cliffs in wet forests in the Upper Hanapepe and Kalalau valleys on Kauai. Curiously, laukahi is one of more than 250 species in the genus. While some consider Plantago species like plantago major to be invasive or ‘weedy,’ Kauai’s plantago princeps is critically endangered with less than 50 individuals known to occur in the wild. One of the most extraordinary botanicals finds in Kauai is the Lysimachia iniki, a rare species of flowering plant in the family Primulaceae known by the common names Wailua River yellow loosestrife and Wailua River island-loosestrife. It is endemic to Hawaii, where there is only one known occurrence existing on the island of Kauai. The plant was federally listed as an endangered species of the United States in 2010.This plant was discovered in 1992, shortly after Hurricane Iniki tore a specimen off the tall cliffs above Kauai’s Wailua River and dropped bits of it where it could be collected. When analysis revealed it was a new species, it was described to science and named for the hurricane. The Hawaiian word `iniki means “sharp and piercing, as wind or pangs of love.”
This is a shrub with hairy green hanging branches growing up to 1.5 meters in length. The woody base grows attached to wet, mossy cliffs. The oval leaves are roughly 3 to 5 centimeters long by 2 to 4 wide. The leaves are packed closely together. Funnel-shaped flowers grow in the leaf axils borne on pedicels up to 2.5 centimeters in length. Each flower has lance-shaped green sepals at the base. The flower petals are dark red at the bases and white at the tips. The stamens are dark red. The fruit is a rounded capsule under a centimeter long. When the plant was described, there were at least 25 individuals. By 2010 there were 40 plants remaining in the single location where it is known to grow, by the “Blue Hole” at the headwaters of the north fork of the Wailua River.
Threats to this species include hurricanes; individuals were damaged during Hurricanes Iniki and Iwa. It is threatened by its small population size, which may cause loss of reproductive vigor and genetic variability and makes the species vulnerable to extinction in any one severe event, such as a hurricane. The cliff-dwelling plant is also vulnerable during flooding and landslides. The habitat is vulnerable to invasion by non-native plant species. Lysimachia, a member of the Primrose family, is often difficult to grow from cuttings. Surprisingly there are only three types of orchids that are native to Hawaii – and these are possibly the least colorful or extroverted orchids that you can imagine. Their technical names are Anoetochilus sandvicensis (the jewel orchid); Liparis hawaiensis (the twayblade orchid); and Platanthera holochila. Orchids, renowned for their exquisite beauty, have captivated botanists for centuries. The island’s mild climate and rich soil provide the perfect conditions for these exotic plants to thrive. There are many different varieties of orchids on Kauai, each with its own unique bloom. The most well-known type of orchid is the dendrobium, which can be found in a variety of colors including white, pink, and purple. Orchids are often used in lei’s, and they are also a popular choice for wedding bouquets. Gardeners on Kauai take pride in their orchid collections, and visitors to the island can enjoy admiring these beautiful flowers. The Kauai “Tropical Milkweed” (asclepias curassavica) plants are a species of evergreen shrub that is native to the Hawaiian Islands. They are commonly found in humid environments, such as rainforests and mountains. The leaves of the plant are large and leathery, with a milky sap that contains toxins that are harmful to many animals. However, the Kauai tropical milkweed is the only known food source for the endangered Hawaiian bee. These bees are essential pollinators of the Kauai plants, and without them, the plants would eventually die out. The relationship between the bee and the Kauai tropical milkweed is an example of mutualism, where both species depend on each other for survival.
Noted for its very long blooming season, the tropical milkweed is an upright evergreen sub-shrub boasting eye-catching clusters of orange-red flowers adorned with yellow hoods from early summer to fall. Flowers are a great source of nectar for butterflies and bees here on Kauai. The blooms occur on upright stems clad with lance-shaped, fresh green leaves. They give way to long, narrow seed pods in the fall. When the seed pods open, they reveal seeds with long, 3-4 in., silvery-white, silky hairs. Milkweed plants are critical to the survival of monarch butterflies’ survival, whose population has plummeted by 90% in the last 20 years. Moving on, we find ourselves in the high-altitude realms of Kauai’s volcanic peaks. Here, against all odds, thrives the awe-inspiring Silversword (argyroxiphium sandwicense). This remarkable plant, endemic to Hawaii, possesses a rosette of silver-gray leaves that glisten under the sun’s gentle caress. Its ability to adapt to extreme conditions has earned it the title of “survivor of the summit,” captivating scientists worldwide. As we venture higher up the mountains, a sense of wonder fills the air. Our botanical expedition takes an unexpected turn as we stumble upon the enigmatic Haleakala Lobelia (Lobelia niihauensis). This rare gem, found only on the remote island of Niihau, enthralls us with its unusual trumpet-shaped flowers. Its mysterious origins and limited distribution make it a true botanical enigma, challenging researchers to unravel its secrets. As we continue exploring rare plants on Kauai we come across the “Kauai Pitcher Plant.” This carnivorous wonder is a sight to behold, with its pitcher-shaped leaves that trap unsuspecting insects. Watching the plant’s delicate yet deadly mechanism in action is a reminder of nature’s intricate balance and the extraordinary adaptations plants can develop to survive in their environment. The first sign of waking up from dormancy, the pitcher plant sarracenia Leucophylla sends out their unusual and beautiful flowers to be pollinated.  Once the flower’s petals have drooped, the plant will begin to send out its pitchers (its ‘mouth’). The resilient Alula (brighamia insignis). This critically endangered species, also known as the “Cabbage on a Stick,” captivates us with its fleshy, tubular flowers that emit a sweet, intoxicating fragrance. With less than 100 individuals left in the wild, our team works tirelessly to protect this botanical marvel from extinction. Brighamia insignis, commonly known as ʻŌlulu or Alula in Hawaiian, is a species of Hawaiian lobelioid in the bellflower family, Campanulaceae. It is native to the islands of Kauaʻi and Niʻihau.

The rare plants of Kauai not only captivate the imagination but also play a vital role in preserving the island’s delicate ecosystem. Conservation efforts are in full swing, aiming to protect these botanical treasures from the threat of extinction. By raising awareness and promoting sustainable practices, Kauai’s rare plants have a fighting chance to thrive for generations to come. So, if you ever find yourself in the enchanting embrace of Kauai, take a moment to appreciate the hidden gems that lie within its verdant landscapes. These rare plants are not only a testament to the island’s natural beauty but also a reminder of the wonders that await us when we take the time to explore and appreciate the world around us. We must embrace to ensure that the legacy of Kauai’s rare plants lives on for generations to come.

Our blog wouldn’t be complete without sharing the breathtaking Kauai Fern Grotto. This hidden gem, tucked away in a secluded valley, reveals a secret sanctuary of lush ferns that create a mesmerizing canopy overhead. The gentle rustling of leaves and the soft sunlight filtering through the dense foliage transport us to a world of tranquility. In this serene moment, our hearts overflow with gratitude for the solace and serenity that nature provides. The beauty and diversity of these plants that are found here remind us of the importance of preserving and protecting our planet. Gratitude fills our hearts for the dedicated efforts of conservationists and the communities that work tirelessly to ensure the survival of these rare plant species. May we continue to appreciate the remarkable beauty that Kauai offers and nurture a deep sense of responsibility to protect our planet’s precious ecosystems.