RETAMA, TEXAS. Retama was a ranching community on a mail route from Edinburg in central Hidalgo County. It was named for the Retama Ranch, which before 1880 operated in the area as part of Macedonio Vela's Laguna Seca Ranch complex-more than forty ranches in the San Salvador del Tule land grant (issued in 1798). The property was subdivided for farming around 1925. Retama is the Spanish word for the Parkinsonia thorn tree, a yellow-flowering tree native to the Rio Grande Valley.