Potatoes were an Earth-based vegetable, often used to make foods such as chips and crisps.
The Doctor was once imprisoned in the Tower of London with Sir Walter Raleigh, who kept going on about the potato, which he'd discovered. (TV: The Mind of Evil [+]Don Houghton, Doctor Who season 8 (BBC1, 1971).)
Peri Brown once found herself in a dimension modelled upon a combination of the Alice in Wonderland book she had been reading and the salad she had been eating. Among the creatures she met in this world were the King and Knave of Spuds, a pair of talking potatoes who nearly executed Peri for the heinous crime of eating vegetables. (COMIC: Salad Daze [+]Simon Furman, DWM Comics (Marvel Comics, 1986).)
The Seventh Doctor cooked a breakfast of fried eggs, bacon, sausages and fried potato slices for Justine and Vincent Wheaton at Smithwood Manor. (PROSE: Cat's Cradle: Warhead [+]Andrew Cartmel, Virgin New Adventures (Virgin Books, 1992).)
The Sontarans were said to look like potatoes, specifically baked potatoes, on several occasions. (TV: Eye of the Gorgon [+]Phil Ford, The Sarah Jane Adventures series 1 (CBBC, 2007)., The Sontaran Stratagem [+]Helen Raynor, Doctor Who series 4 (BBC One, 2008)., The Last Sontaran [+]Phil Ford, The Sarah Jane Adventures series 2 (BBC One and CBBC, 2008)., The Snowmen [+]Steven Moffat, Doctor Who Christmas Special 2012 (BBC One, 2012).)
Learning that a Slitheen feared Clyde Langer's cold chip sandwich, Maria Jackson briefly suggested the Slitheen were allergic to potato before Sarah Jane Smith recalled seeing a Slitheen eating a sandwich. (TV: Revenge of the Slitheen [+]Gareth Roberts, The Sarah Jane Adventures series 1 (BBC One and CBBC, 2007).)
In 2009, potatoes were one of many fruits and vegetables sold in Mr. Cousins' greengrocers. (PROSE: The End of the Rainbow [+]Jacqueline Rayner, Doctor Who Storybook 2010 (Doctor Who Storybook, 2009).)
After Gwen Cooper and Rhys Williams hid in a truck filled with potatoes to escape to London, Gwen said, "Rhys, you are not eating uncooked potatoes", after Rhys had asked her for a knife. (TV: Children of Earth: Day Two [+]John Fay, Torchwood series 3 (BBC One, 2009).)
in 2018, Ramón Salamander's chef Griffin, after being unimpressed with Victoria Waterfield's recipe for Kaiser pudding, assigned Victoria to peel potatoes. (TV: The Enemy of the World [+]David Whitaker, Doctor Who season 5 (BBC1, 1967-1968).)
In 2075, the First Doctor, John and Gillian used potatoes as makeshift weapons to defeat the space pirates on Anastas Thrax's space station. (COMIC: The Hijackers of Thrax [+]TVC comic stories (1965).) Later, in 1800, the Tenth Doctor similarly used potatoes in combat. Onboard an American schooner in the Caribbean Sea during the dying days of the Quasi-War, he used potatoes, turnips and molasses to create an organic mixture capable of clogging proton cannons. (COMIC: Second Wave [+]Steve Cole, DWBIT comic stories (GE Fabbri Ltd, 2007).)
Potatoes were among the plants kept in the plant museum near Brittanicus Base. (TV: The Ice Warriors [+]Brian Hayles, Doctor Who season 5 (BBC1, 1967).)
The Alovians believed all problems could be solved with potatoes. (PROSE: Doctor Who and the Krikkitmen [+]Error: Code 2 - no data stored in variables, cache or SMW.)