Oak Grove is an unincorporated community in Washington Township, Starke County, in the U.S. state of Indiana.[1] Quick Facts Country, State ...Oak GroveUnincorporated communityOak GroveShow map of IndianaOak GroveShow map of the United StatesCoordinates: 41°17′16″N 86°29′10″WCountryUnited StatesStateIndianaCountyStarkeTownshipWashingtonElevation[1]738 ft (225 m)Time zoneUTC-6 (Central (CST)) • Summer (DST)UTC-5 (CDT)ZIP code46511Area code574GNIS feature ID440400[1]Close References [1]U.S. Geological Survey Geographic Names Information System: Oak Grove, Starke County, Indiana This Starke County, Indiana location article is a stub. You can help Wikipedia by expanding it.vteWikiwand - on Seamless Wikipedia browsing. On steroids.