World’s tallest corn plant takes the world record at 45 feet

Imagine being lost in a corn maze, stalks of maize towering over your head at 12 feet tall. Now imagine the corn is about 45 feet tall.

While you can’t actually find a maze made from corn that tall, if you go to Costa Rica, you can find one stalk that stretches that high. There, plant breeder Jason Karl has set the record for tallest corn plant at 45 feet tall.

It’s not the first time he’s set the world record — he first managed the feat in 2011, with a 35-foot-tall plant grown on his family’s farm. He’d been experimenting with growing corn as tall as possible since his teenaged years.

“It’s never been done before,” he told The Scientist. “No one would try it because it makes corn tall — too tall. People are not interested in super-tall corn. However, it’s interesting for basic research.”

Throughout his college years Karl studied the mutations in corn that would cause the biggest possible internode length (meaning the length between leaves on a stalk). Along the way he’s found several factors that make his corn taller, like growing within a greenhouse, which, according to The Scientist, works because the plastic or glass affects the spectrum of light hitting the leaves. He focused on strains that were “night-length reactive,” meaning they were best suited for long days and short nights. He also found a particularly tall-growing strain from southern Mexico, called Chiapas 234.

His original world record was set by changing environmental conditions like these, but Karl then broke into plant breeding. He bred Chiapas corn with a plant carrying the Leafy mutation, a mutation that adds extra internodes, and back-bred the hybrid into following generations of Chiapas plants. He eventually incorporated other mutations that increased the number of internodes, like the delayed flowering mutation.

To truly soar to new heights, Karl’s corn needed a longer growing season. In 2017 he moved from New York to Costa Rica, where he set up a makeshift greenhouse that would house his plants and support them as they grew to unprecedented heights.

There he grew the latest record setter. At 45 feet tall, Karl’s latest plant has more than 80 internodes. The Scientist reports that unmodified Chiapas corn grown under normal conditions would have closer to 25 internodes at best.

Optimistic, Karl has already built a 55-foot-tall plastic greenhouse for his next attempt.