Police visited the semi-rural property at Coromandel East to conduct a search on Monday.
Officers said they found and seized 18 cannabis plants that were being grown hydroponically.
Police said they also seized about 680 grams of dried cannabis, two gel blaster firearms, about 35 grams of a white powder suspected to be cocaine, hydroponic equipment and a large quantity of cash.
A 53-year-old man and a 20-year-old man, both from the Adelaide suburb of Coromandel East, were arrested at the property.
They have both been charged with cultivating cannabis, theft of electricity, possess prescribed equipment, trafficking in controlled drugs namely cocaine and cannabis, money laundering and possess firearms without a licence.
The men have been refused bail and will appear in the Adelaide Magistrates Court on Tuesday.
