ALL EARS: Jason Karl grows giant maize in specially constructed greenhouses in Costa Rica. COURTESY OF JASON KARLJason Karl has been growing corn since he was a teenager. Starting in 1996, he began planting the crop on his family’s farm in Olean, New York, and soon grew curious about how tall he could make it grow. So he started experimenting.
“Seeing how tall corn can grow comes down to internode length and quantity,” Karl explains—in other words, the number of leaves a stalk has and the distance between those leaves. He learned early on that growing seedlings in a greenhouse greatly increases internode length, in part because the glass or plastic shifts the light spectrum reaching the plant’s leaves. He also learned that certain strains of corn were “night-length reactive,” meaning that the plant increases its number of internodes when grown in a light regimen of long days and short nights. Chiapas 234, an already-tall corn variety from southern Mexico, develops twice as many.
Karl carried on his corn-growing experiments at home while he was in college at Cornell University, a couple of hours’ drive ...
