Oh, give us pleasure in the flowers to-day;
And give us not to think so far away
As the uncertain harvest; keep us here
All simply in the springing of the year.
Oh, give us pleasure in the orchard white,
Like nothing else by day, like ghosts by night;
And make us happy in the happy bees,
Frost is describing how the “uncertain harvest” alludes to life. How waiting and being patient like how a harvest moon will illuminate through the night which allows you to work and make life springing towards something new and improved. 

A Prayer in Spring