"But unless you watch your step, you might just find that my hand slips ...right over your evening pumpkin juice. And then Potter ... then we'll find out whether you've been in my office or not."
-- Snape threatening to spike the pumpkin juice with Veritaserum (GF27)
"Tea? Coffee? Pumpkin juice?"
-- Dolores Umbridge, trying to trick Harry into taking Veritaserum
A mundane vegetable used for food, drink, and ornamental purposes.
- Hagrid maintains a pumpkin patch outside his hut, which produces the pumpkins used to decorate the Great Hall for the Hallowe'en feast. Although the plants aren't inherently magical, Hagrid gives them some "help" so that the pumpkins swell to the size of garden sheds by the time the feast rolls around (CS6,CS8). See also Pumpkins R Us.
- Pumpkin juice is a staple drink around the Hogwarts table (CS5, PA6,GF12,OP11).Professor McGonagall summoned sandwiches and pumpkin juice to Snape's office while the boys waited after crashing the Ford Anglia into the Whomping Willow (CS5).
- Pumpkin juice is sold "ice-cold" from the trolley on the Hogwarts Express (CS5) along with a treat called pumpkin pasties (PS6,OP10). A variation on the pasties is pumpkin tart, served for the Sorting Feast in third year (PA5).
- When Gryffindor beat Ravenclaw at Quidditch, they were planning to drink some pumpkin fizz before finding the Fat Lady's painting had been attacked (PA13).
- Hermione and Harry rescued Buckbeak the hippogriff from Hagrid's pumpkin patch, saving his neck (PA21).
- Pumpkins as candle holders were among the Halloween decorations at Hogwarts (PS10,PA8). In fourth year, "hundreds of carved pumpkins leered from every corner" (GF16).
- The blast-ended skrewts "rampaged" in Hagrid's pumpkin patch, withering the vines (GF21).
- Snape threatened once to put a drop of Veritaserum in Harry's pumpkin juice to force the truth out of him (GF27)
- Sirius Black in dog Animagus form waited in Hagrid's pumpkin patch after the Triwizard Tournament (GF35).
- Harry pretended to put a drop of Felix Felicis in Ron's pumpkin juice to boost his courage for Quidditch try-outs (HBP14).
- Hagrid buried Aragog the Acromantula "just beyond the pumpkin patch" (HBP22)
- Pumpkin juice was served at Bill and Fleur Weasley's wedding (DH8), and their home Shell Cottage was also stocked with plenty of it (DH27).
- The Beauxbatons carriage in the snow reminded Harry of a "frosted pumpkin" (GF23).
- When Dumbledore overwhelmed Umbridge, two Aurors, and Cornelius Fudge, a rumor went around that Fudge ended up with "a pumpkin for a head" (OP28).
- On his way to kill the Potters in Godric's Hollow, Voldemort saw two children dressed as pumpkins for Halloween. He scared one of them, but chose not to kill him (DH17).
Pumpkin juice does not seem to be connected with potions.
From the Greek pepon (πέπων) “large melon"
On Halloween in the United States, pumpkins are traditionally carved into "jack-o-lanterns" with a face lit up by a candle. But in England and Ireland the traditional vegetable used on All Hallow's Eve was the turnip or the related swede (rutabaga). In literature, Washington Irving told the story of the Headless Horseman who chased Ichabod Crane away from Sleepy Hollow by throwing a carved pumpkin at him. In L. Frank Baum's Wizard of Oz books, there is a character named "Jack Pumpkinhead, and in Tim Burton's film "The Nightmare Before Christmas," the "Pumpkin King" is named Jack Skellington. And of course the most famous of all is Charles Schultz's holiday creation "It's the Great Pumpkin, Charlie Brown" with Linus Van Pelt and Lucy Brown missing tricks or treats, spending Halloween in the "most sincere" pumpkin patch. source: Wikipedia