A Horatio, Ark., man was recently charged with growing marijuana in flower pots in a shed behind a house.

But before the arrest was made, the South Central Drug Task Force was allowed to let the plants grow and mature to make sure they were marijuana, said law enforcement authorities.

Samuel Alexander, 47, of Horatio, was charged with manufacturing of a controlled substance—marijuana. He was allegedly growing 22 marijuana plants in pots behind a house in a shed.

The charge is a Class C felony with a potential sentence of 4 to 10 years in prison and a maximum...