Spring Equinox 2025 Australian Time. Spring equinox 2025 (beginning of astronomical spring) on the day of the spring (march) equinox, the sun crosses the celestial equator, moving along the ecliptic. The beginning of spring corresponds to the spring equinox, which usually falls september 21st or 22nd in the southern hemisphere.
Spring isn’t even a season in some places. It is also the point in the calendar where the day length is more or less equal to the length of the night.