The Fire Seed Caves were a section of Rubeus Hagrid's garden in the Forbidden Forest, so named because they were where Rubeus Hagrid grew his Fire Seed Bushes. Other than the Fire Seed Bushes, the caves were infested with Doxies, Streelers, Venomous Tentaculas, and Fire Crabs. Massive subterranean waterfalls ran through sections of the caves. Though mostly natural in environment, the Fire Seed Caves showed some signs of Hagrid's presence in them, most notably wooden portcullises blocking off certain areas, as well as torches, wooden carts, barrels, and other objects.
In 1991, Hagrid, who had recently acquired a Norwegian Ridgeback egg from a hooded stranger, required Fire Seeds to increase the heat in his fireplace and hatch the egg properly. As he could not leave the fire unattended, he sent Harry Potter into the Fire Seed Caves to collect seeds for him. Harry successfully collected the required number of seeds and returned them to Hagrid.