Continuity mistake: When Annie and Ray are laying in the newly completed ball field, and Annie is drinking a glass of wine, it is sunset. The sun has gone down and the sky is just the faintest of pink on the horizon, the rest of the sky is a strong blue tone. Yet, when the camera cuts to a long shot, same angle of Ray and Annie, the horizon is now a brilliant red-orange taking up nearly a third of the sky.
Trivia: During the filming of the cornfield scenes where Ray first hears the voice, the filmmakers had problems with the corn growing. When they initially wanted to film the scenes the corn was too short, so they waited a couple of weeks. When they were ready to shoot, the corn was too tall. Kevin Costner had to walk on wooden planks, so he could be seen in the cornfield (Director Phil Alden Robinson discussed this in the 10th anniversary edition of the film).