Orchard Glen Park.
In south Fargo there's a place that has been changed from vacant land into a free public apple orchard and park. Walking through the park when the trees are blooming is like walking through the Museum of The Family Photo. For every tree that is blooming there is a group using it as a background. Since there is only about a week long time frame when the trees are in full bloom the park can get pretty packed during high traffic times. It's still a great place to go see especially later in the day or early in the morning.
Side note: I hope the people that throw their empty water bottles on the ground in places like this experience a very annoying mild inconvenience. Like stubbing their toe in the dark, or missing the last step walking up the stairs.