The arraignment was originally scheduled for April 30.
A federal indictment unsealed Monday in Lexington charges Farmer with using his state position to obtain thousands of dollars' worth of gifts, hotel rooms, clothing and computers. It also charges him with hiring friends who did little or no work for the state.
The indictment says that throughout his tenure as agriculture commissioner from 2004 to 2012, Farmer wrongfully used public funds and state resources to obtain goods and services for himself and his family.
If convicted on all counts, Farmer faces prison time and a $250,000 fine.
Farmer's attorney, Guthrie True, said Monday he is reviewing the indictment and saw no surprises in it.