How Much Can a Giant Waterlily Hold? See One Carry 183 Pounds Before Sinking, Winning a Social Media Contest
Now in its third year, the Waterlily Weigh-Off invites public gardens and zoos to show off the strength of their aquatic plants
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Giant waterlilies are known for their gorgeous white or pink flowers and green leaves, which float serenely atop the surface of lakes and streams.
At first glance, these aquatic plants might seem delicate. But in reality, they’re incredibly strong. Earlier this month, the leaf of a giant waterlily at Florida’s Bok Tower Gardens supported 183 pounds before it started sinking, beating out other global competitors to be crowned champion of the 2025 Waterlily Weigh-Off.
The weigh-off, which is now in its third year, is an annual social media contest organized by Denver Botanic Gardens. To enter the competition, horticulturists at public gardens and zoos across the globe film themselves stacking weighted objects atop one of their giant waterlily pads (or smaller lilies), noting the total weight the leaf was able to hold before dipping beneath the surface.
According to Denver Botanic Gardens, the contest is a “playful opportunity” to educate the public about aquatic plants, specifically Victoria amazonica, Victoria cruziana and a mash-up of those two giant waterlily species called the Victoria ‘Longwood Hybrid.’ The leaves—also known as platters or pads—of these species can measure up to ten feet across.
The pads can hold such an impressive amount of weight because of their structure. The bottom of each leaf consists of a “highly engineered network of radiating ribs and cross-veins,” per Denver Botanic Gardens. The ribs and veins form stiff compartments that trap pockets of air, which helps distribute weight across the leaf. The tops of the pads also have upturned edges, offering a barrier that can prevent water from spreading across the surface as the leaf gets weighed down.
Scientists studying the mechanics of the plants’ unique leaves suggest they could one day help improve the engineering, design and construction of manmade buildings, especially floating structures.
Fun fact: An enormous waterlily hidden in plain sight
In 2022, scientists discovered the waterlily species Victoria boliviana after realizing it was distinct from the others. Then, the new species was certified as the biggest waterlily in the world.
But giant waterlilies are not just strong—they’re also fierce. The bottoms of the leaves are covered in sharp, thorny spines, which help protect the plant from predators and encroachment from other plants.
“Underneath is kind of cool, because they’re very dangerous,” says Kevin Bendetti, a horticulturist at Brookgreen Gardens in South Carolina, to the Post and Courier’s Lauren Leibman.
This year, participants used everything from bricks and gin bottles to tea cakes and toy frogs to test the strength of their giant waterlily pads. The contest, which took place from August 18 to 24, included more than 40 participants in nine countries.
This year’s runner-up was a giant waterlily at Missouri Botanical Garden, which held 182 pounds, just one pound shy of the winner.
Third place went to a specimen at the Huntsville Botanical Garden in Alabama, which held 176 pounds. The team there kept piling on sandbags until they found the limit of their hybrid waterlily, which they’ve nicknamed “Tori.”
“We just kept adding and I was like, ‘OK, we’re over 100 pounds, 120 pounds, OK, we’re still going.’ So it was amazing to see how much weight it could hold,” says Max McKeown, the garden’s horticulture manager, to WHNT’s Cristina Byrne and Emily Moessner.
Denver Botanic Gardens’ own entry came up short, only holding 50 pounds before sinking. However, staffers there don’t mind the outcome one bit. They’re just thrilled to see how popular the contest has become, and they hope it will ultimately help attract more visitors to public gardens and zoos around the globe.
“I’m really proud of what we have been able to build out of this silly little idea we started,” says Vanessa Callahan, assistant manager of learning engagement at Denver Botanic Gardens, to KMGH-TV’s Ethan Carlson. “[The participating gardens are] just showing so much creativity, so much storytelling, so much earnest about them, experiences and personality, and I’m having so much fun watching it.”
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