The road heads east through pecan orchards and fields of Mesilla Valley for 0.54 miles (0.87 km) before turning northeast.

At 0.870 miles (1.400 km) the highway crosses the Rio Grande river over a 476.1-foot-long (145.1 m) bridge, built in 1941.

The road continues northeast and crosses railroad tracks of El Paso Subdivision of BNSF Railway right before reaching its eastern terminus at intersection with NM 478.

The section occupied by modern day NM 189 was initially built in 1940-1942 as part of the surge in infrastructure projects across the United States to support wartime logistics and troop movements as a connector between NM 28 and US 85 in Vado.

In 1988, the New Mexico Department of Transportation (NMDOT) went through a radical road renumbering program, and this stretch was designated as NM 189.