In this episode, Adam tells Almanzo they should get married on his and Mary's wedding anniversary, which is the fifteenth of August, by what was mentioned in the episode "The Wedding". However, the real Almanzo and Laura Wilder got married on the twenty-fifth of August, in 1885, in De Smet, Dakota Territory.
Almanzo claims he and Laura have to wait another 2 years to get married since he can't put a roof over her head. How would there have been a roof in that field even if the crop grew. There wasn't a single tree for a log cabin.
Almanzo mentioned to Laura about her wearing his engagement ring. However, engagement rings weren't available until the 1900s.
In this episode, set in 1885, Charles tells Almanzo, "Being positive is being wrong at the top of your voice." It is a paraphrase of an entry from Ambrose Bierce's "Devil's Dictionary," first published as "The Cynic's Word Book" in 1906.