When Does Spring Begin 2025. This date marks the spring equinox in the northern hemisphere. Since the seasons vary in length, the start date of a new season can fall on different days each year.

But what exactly is the vernal equinox, and why does it begin this year at 10:01 a.m. Here are the equinox and solstice dates—plus, answers to common questions about the seasons of the year in north america.