After receiving information, Solothurn police searched the couple’s house in November and uncovered a plantation of 900 marijuana plants in the basement.
Some of the hemp plants were ready to harvest, said police, who added that officers ensured the entire plantation was destroyed.
The force released a photo of bushy plants, some nearing the ceiling in height.
It appeared that the couple were well armed to deal with intruders or anyone seeking to steal the pot.
Police said they discovered more than 100 weapons in the house “including knives, stun guns, firearms and ammunition of all kinds”.
Subsequent investigations have showed that many of the weapons were not registered.
The sale or possession of some of the arms is illegal in Switzerland.
The man and woman, whose ages were not revealed, face charges of violations of narcotics and weapons laws, police said.
Biberist is a town with a population of 8,000 people, about 30 kilometres northeast of Biel.