May Day
One of the four "fire festivals" or "greater sabbats".  Its significance focuses on fertility.  In Ireland, the hawthorn tree flowers from May to early June; it is known as the May Tree.

 “All wanted then was to fill my arms
with sharp flowers,
to seem, from a distance, to be part of
that ivory, downhill rush. 
But I knew,
…the custom was
not to touch hawthorn.
… So I left it
stirring on those hills
with a fluency
only water has.
… in
the unmarked lights of a May dusk --“
White Hawthorn in the West of Ireland
Evan Boland

Never give all the heart, for love
Will hardly seem worth thinking of
To passionate women if it seem
Certain, and they never dream
That it fades out from kiss to kiss;
For everything that's lovely is
But a brief, dreamy, kind delight.
O never give the heart outright,
For they, for all smooth lips can say,
Have given their hearts up to the play.
And who could play it well enough
If deaf and dumb and blind with love?
He that made this knows all the cost,
For he gave all his heart and lost. 
Never give all the Heart
W.B. Yeats