Harry Plums Wholesale Fruit is an abandoned business in Doherty, San Fierro. There is a black Boxville parked between the alley which the player can trigger the Burglar missions. The loading bay serves as the hideout entrance. The business is inaccessible to the player and plays no role in the storyline whatsoever.
The term 'Harry Plums' also sounds remarkably like 'Hairy Plums', and considering Rockstar's past with sexual innuendos within the GTA universe, it seems more than a coincidence that 'Hairy Plums' is also a slang term for a hairy scrotum.