Plants are organisms from the kingdom Plantae. Most are multi-cellular and obtain their energy from sunlight using photosynthesis. There are currently around 320,000 species of plants which are found all over the world. Plants form the basis of virtually every ecosystem in the world and they are incredibly important to millions of animals. Animals rely on them for both a source of food and a place to live.
Without plants there would be no forests, no meadows, no ground cover – nothing but a barren landscape. Plants are also important to us humans too. They produce seeds, grains, and fruit and many species are grown and harvested specifically as a source of food. Plants vary in size from tiny flowers to giant trees which tower over everything else. But just how big can they get? Join us as we discover some of the largest plants in the world!
10. Largest Plant: Stinking Corpse Lily
The first plant on the list is the stinking corpse lily, which is the largest individual flower. Stinking corpse lily flowers (Rafflesia arnoldii) grow to a diameter of approximately 3 ft 3 in and weigh up to 24 pounds. They are native to Sumatra and Borneo where they typically occur in rainforests, and consist of a wide flower which is a deep reddish color. They are particularly unusual as they appear to lack any recognizable leaves, stems, or roots. Instead, they attach themselves to a host plant and essentially steal water and nutrients from them. The flower itself takes around 21 months to fully grow and then only lasts for one week. As their name suggests, stinking corpse lilies produce a strong, pungent odor which smells like rotting flesh.
9. Largest Plant: Hope’s Cycad
The tallest known species of cycad is Hope’s cycad (Lepidozamia hopei) which can reach heights of more than 50 feet. Cycads are seed-bearing plants which have a woody trunk and stiff evergreen leaves which can be up to 6 feet long. Hope’s cycad is endemic to the the state of Queensland in Australia where they grow in moist, shady areas in gullies and along creek beds. They are extremely slow growing – typically growing less than 1 inch per year – meaning that they take several hundred years to mature. The oldest individual specimens are estimated to be around 1,000 years old!
8. Largest Plant: Kwango Giant Cycad
From one of the slowest growing cycads we now move on to the fastest which is the Kwango giant cycad. Kwango giant cycads (Encephalartos laurentianus) has stems which grow to around 60 feet long and 4 feet thick. They also have the longest leaves of any cycad at around 23 feet. Kwango giant cycads are native to Angola and Congo where they typically grow along the Kwango river, hence their name. They eventually grow so large that they can no longer remain straight and begin to grow along the ground instead.
7. Largest Plant: Norfolk Tree Fern
The largest fern is the Norfolk tree fern which reaches 66 feet high and has fronds which are around 16 feet long. Norfolk tree ferns are usually evergreen but their stalks are covered in whitish-brown to orange-brown scales. The trunk generally becomes smoother as the tree ages. However, it can sometimes have a number of oval-shaped marks from fallen fronds. Norfolk tree ferns (Sphaeropteris excelsa) are endemic to Norfolk Island where they occur in subtropical rainforests. Although the forests on Norfolk Island were once vast, they have now been reduced to a single forested area which is part of a national park. Therefore, Norfolk tree ferns are protected within this area.
6. Largest Plant: Taliplot Palm
One of the largest palm trees and the palm tree with the largest inflorescence (cluster of flowers) is the talipot palm. Talipot palms (Corypha umbraculifera) are native to India and Sri Lanka but are also grown in several other countries. They reach heights of up to 82 feet and have stems with a diameter of 4.3 feet. They are fan palms and their leaves can be up to 16 feet wide. Their inflorescence are usually 20 to 26 feet long and clusters can contain up to several million small flowers. Incredibly, they only flower once in their life – usually sometime between the age of 30 and 80. Once they have flowered it takes around one year for the fruit to mature, after which the entire plant dies.
5. Largest Plant: Giant Highland Banana
Growing deep in the mysterious montane mountains of New Guinea is one of the most unusual plants – the giant highland banana. They typically grow in wet areas in ravines or at the edge of highland swamps at elevations between 4,265 and 6,560 feet. Giant highland bananas (Musa ingens) are often mistaken for trees, but they are in actually herbs – making them the largest herbaceous plant in the world at a staggering 98 feet tall. What looks like a trunk is actually just tightly rolled petioles (stalks). These stalks hold around 12 leaves which appear as a crown at the top. Giant highland bananas produce up to 300 individual fruits in a single cluster.
4. Largest Plant: Giant Bamboo
One of the largest bamboo species in the world is giant bamboo which reaches and incredible 138 feet high. Giant bamboo (Dendrocalamus giganteus) are native to southeast Asia where they grow in forests and on river banks at elevations up to 6,600 feet. Giant bamboo grows in large clumps which are situated close together. They are straight and grayish-green but turn brownish green as they dry. Giant bamboo has huge culms that reach a diameter of one foot wide. It is also fast growing and can grow up to 12 inches per day. Giant bamboo has many uses and is used for making boat masts, water pipes, bamboo houses, furniture, and paper to name a few.
3. Largest Plant: Mountain Ash
Classed as the tallest flowering plant in the world, mountain ashes (Eucalyptus regnans) reach a massive 330 feet tall. They are native to Tasmania and Victoria, Australia where they grow in mountain regions that receive more than 39 inches of rainfall per year. Their range varies between sea level up to 3,600 feet on the Errinundra Plateau. Mountain ashes are evergreen trees and have straight trunks and glossy green curved leaves. Their flowers are arranged in groups of between 9 and 15 buds which are oval-shape and around 0.25 inches long. They flower between March and May with white flowers that have pyramid-shaped seeds.
2. Largest Plant: Coast Redwood
One of the largest trees in the world is the coast redwood which reaches an amazing 379 feet high. Coast redwoods (Sequoia sempervirens) are the only living species in the Sequoia family group and are also one of the oldest trees – living approximately 1,200 to 2,200 years. They are native only to a narrow strip of land along the Pacific coast of North America, mainly at elevations between 100 and 2,460 feet. Coast redwoods are evergreen trees with straight trunks and scale-like leaves. Their branches droop slightly which makes them appear as a conical crown. Coast redwoods are one of the most sought after trees due to their valuable timber. However, they are now an endangered species.
1. Largest Plant: Poseidon’s Ribbon Weed
The newly crowned largest plant in the world is the Poseidon’s ribbon weed, an Australian seagrass which covers approximately 77 square miles in one single plant. Up until May 2022, Poseidon’s ribbon weed wasn’t in the running for the largest plant, but this fascinating phenomenon has occurred because the plant has cloned itself. That’s right, Poseidon’s ribbon weed (Poseidon australis) has repeatedly cloned itself to become the world’s largest living organism. It was discovered in Shark Bay, Australia and has reportedly taken 4,500 years to reach the massive size that it is today. Poseidon’s ribbon weed typically occurs at depths of between 3ft 3in to 49ft 3in in the waters around the southern coast of Australia and has bright green ribbon-like leaves. Its ability to clone itself is thought to be the reason that it recovered so easily after the heatwaves of 2010 and 2011 which impacted many seagrass meadows.