The Naked Jungle (1954) on Netflix

It's 1901. At 19, tough, stubborn Christopher Leiningen came to South America and built levees to claim thousands of acres of Rio Negro river land for a chocolate plantation. Now 34, with no knowledge of women, he recruits a mail-order bride in New Orleans. She's beautiful, independent, and arrives ready to be his stalwart helpmate; however, no one has told him she's a widow. He rejects her. During the next week, as she awaits the boat to take her back to the US, they learn that legions of army ants will strike in a few days' time. She joins the fight to save the plantation; their courage and his probable loss of all he's worked for may crack his resolve to send her away.