Cannabis with an estimated value of £197,000 was discovered following two separate searches on Thursday.
In the first, a car travelling north on the A74(M) was stopped by a police patrol near Lockerbie and a haul found, believed to have a street value of £120,000.
Police Scotland state a 28-year-old man from Birmingham was arrested.
In the second, thought to be unconnected, incident, cannabis to the value of around £77,000 was recovered after a house in the Eskdalemuir area was searched.
Two men, a 38-year-old from the local area, and a 57-year-old from Edinburgh were arrested.
Police say reports have been forwarded to the Procurator Fiscal at Dumfries.