From the Super Mario Wiki, the Mario encyclopedia
The Beanstalk is an enormous plant found in Fungi Forest in Donkey Kong 64. It grew from a small, pink seed found by Tiny Kong. Tiny finds the seed inside a tree stump after she defeats a group of Purple Klaptraps. After that, she must plant the seed in some fertile soil near Funky's Store, where it grows into the Beanstalk almost instantly. A Golden Banana is on top of the Beanstalk. To reach it, Tiny must use Mini-Monkey and perform on a Music Pad to summon Squawks, who carries her up to the Golden Banana.