"When the April wind wakes the call for the soil, I hold the plough as my only hold upon the earth, and, as I follow through the fresh and fragrant furrow, I am planted with every foot-step, growing, budding, blooming into a spirit of spring."
-  Dallas Lore Sharp, 1870-1929 

"In the spring I have counted one hundred and thirty-six different kinds of weather inside of four and twenty hours." 
Mark Twain

"Every spring is the only spring - a perpetual astonishment."  Ellis Peters

"April hath put a spirit of youth in everything."
William Shakespeare 

"Anyone who has a bulb has spring.  Bulbs don't need much light; they don't need good soil; and they don't need cosseting.  They are, in fact, the horticultural equivalent of cats; self-contained, easy-care, and supremely suited to living in New York."
Author Unknown

"Spring has returned.  The Earth is like a child that knows poems." 
Rainer Maria Rilke

"You start in April and cross to the time of May
One has you as it leaves, one as it comes
Since the edges of these months are yours and defer
To you, either of them suits your praises.
The Circus continues and the theatre's lauded palm,
Let this song, too, join the Circus spectacle."
Ovid, Fasti (V.185-190, CE)