Pumpkin science


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.

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.

Comments

  1. Rich Woods says

    That’s like daily adding a two-year-old child to its mass.

    Look, the sacrifice is worth it, OK? And the neighbourhood has been so much quieter this year.

  2. says

    I find this always so sad. Zoos need to go.
    On another note Laura Ingalls Wilder’s husband Almanzo talked about raising a milk-fed pumpkin, where he made a slit in the stem and ‘fed’ the pumpkin milk, creating a HUGE pumpkin that won at the fair both for size and sweetness of taste if a paler color that the other entries. Anyone ever try this?

  3. says

    “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.”

    They could kick Donald Trump’s head around, that’s pretty pumpkin like.

  4. wzrd1 says

    Neve4 had much use for giant pumpkins, but at least science studied the a bit and will likely study them a bit more to learn more about the transport system and its development.
    Personally, I prefer 6 – 8 inch pie pumpkins, which tend to be rare in many supermarkets.
    More’s the pity, as one pie pumpkin can make a few pies or a hell of a lot of soup!
    I switched from baking mine to 15 minutes in a pressure cooker.

  5. naturalistguy says

    One year in our garden we had a volunteer pumpkin grow out of our raised bed and start growing into the yard, and before we knew it the damn vining thing was twenty feet long. It’s like pumpkins are the triffids of gourds!

  6. lumipuna says

    On another note Laura Ingalls Wilder’s husband Almanzo talked about raising a milk-fed pumpkin, where he made a slit in the stem and ‘fed’ the pumpkin milk, creating a HUGE pumpkin that won at the fair both for size and sweetness of taste if a paler color that the other entries. Anyone ever try this?

    Sounds like a tall tale. If you actually managed to inject substantial amounts of milk into the plant’s phloem, it’d likely mess up the plant’s metabolism and trigger a bacterial infection. Plants can utilize externally fed sugar, but hardly in lactose form, let alone the fats and proteins of milk.

  7. says

    @9 well blow me down! Looked it up after reading your post and people actually do the milk fed pumpkin thing! Guess it works too! Go figure.

  8. hillaryrettig says

    I would have never guessed that the capacity of the circulatory system would be the limiting factor!