I know there is an official date for the start of Spring, but for me, spring officially begins on Easter. I’m not religious, but for some reason, the turn of the season isn’t really official without a holiday of some kind to mark the occasion. And Easter, despite the protests that some people like to lodge, is really based on a pagan festival of spring anyway.
If you’ve ever noticed that the word “Easter” resembles the word “east” and “eastern” it’s because they derive from the same root:
Old English Easterdæg, "Easter day," from Eastre (Northumbrian Eostre), from Proto-Germanic *austron-, "dawn," also possibly the name of a goddess whose feast was celebrated in Eastermonað (the Anglo-Saxon month corresponding with April), from *aust- "east, toward the sunrise" (compare east), from PIE root *aus- (1) "to shine," especially of the dawn.
Bede writes that Anglo-Saxon Christians adopted her name for their Mass of Christ's resurrection. (Online Etymology Dictionary)
Spring represents the resurrection of the earth, plants, and life generally after their long dormancy through the winter, awakened by the warming sun and longer days. The dark, lean times would be ending and the bright, abundant times would be returning. The motivation to link these the heathen and christian concepts is clear.
I enjoy the blending of the two traditions. And I love how this song conveys how closely we are tied to the rhythms of the natural world, its seasons, and the creatures we share the Earth with. Easter weekend for me is when I can breathe a sign of relief, watch the grass green up, see the daffodils open, and finally take the plows off the tractor and RTV. Winter’s come and gone.