May by Mark Van Doren

All at once it is here.
But then it takes its time.
The best month is the longest,
Thank God: the slow smile,
Loving its own dearness
Daily, with delicate changes
As more and more is remembered
Of what again must be:
Spring turning to summer
And yet remaining spring;
Trees still transparent;
Leaves clear and green;
Everywhere flowers;
Ferns--look--in a ring;
And birds flying over
As if this were forever.