If you’ve ever wondered how giant pumpkins can get so big, Bethany Brookshire has the answer.
Giant pumpkins need a lot of water and sugar, and they need it fast. A typical giant pumpkin grows from seed to huge orange squash in only 120 to 160 days. At peak growth, it’s putting on 15 kilograms (33 pounds) every day. That’s like daily adding a two-year-old child to its mass. And all of that mass must move through the stem, Savage notes. Most of the time, the stem is so narrow that you can still easily get your hands around it.
To study how pumpkin stems transport so much food and water, she asked growers of giant pumpkins to donate small slivers of their competition fruits. She also got any pumpkins that burst before they could be judged. She even got small pumpkins that farmers had rejected before they plumped up. (To grow a massive pumpkin, farmers will only let one pumpkin on each plant reach full size.) She also grew a few of her own.
Savage took a close look at the stems, leaves and pumpkins and then compared them to those from other large squashes. Giant pumpkins don’t produce more sugars, she found. And their xylems and phloems don’t work differently. The titans just have more transport tissue. “It’s almost like there’s this mass growth of the vascular tissue in [the] stem,” she says. Extra xylem and phloem help the stem pump more food and water into the fruit, leaving less for the rest of the plant.
It’s a transport difference! We don’t appreciate the importance of transport in multicellular organisms enough.
Of course, what you really want to see are elephants smashing giant pumpkins.
They did the mash! Big thanks to giant pumpkin growers Larry Nelson and Jim Paino for the gourd time! pic.twitter.com/GSY23qJoBV
— Oregoth Boo (@OregonZoo) October 23, 2020
Hey, I just realized that we didn’t carve a pumpkin for our house this year! I guess the nonexistent trick-or-treaters won’t have anything to kick around.