Leaves Compared with Flowers - A lesson and poem from Robert Frost

I am reading Robert Frost and reflecting upon this.  What's the point of loving flowers, which we can only see during the day. We must learn to appreciate the leaves which we hear rustle in the dark and bark which we can lean against in the dark. Flowers don't support you in the night. Barks do. You don't hear flowers rustle at night.  You hear leaves.  Frost may have been a slave to a springtime passion for the earth once; but now his has better appreciation. Leaves are his darker mood!  

Leaves Compared with Flowers
- Robert Frost

A tree's leaves may be ever so good
So may its bark, so may its wood;
But unless you put the right thing to its root
It never will show much flower or fruit.

But I may be one who does not care
Ever to have tree bloom or bear
Leaves for smooth and bark for rough
Leaves and bar may be tree enough

Some giant trees have bloom so small
They might as well have none at all
Late in life I have come on fern
Now lichens are due to have their turn

I bade men tell me which in brief
Which is fairer, flower or leaf.
They did not have the wit to say,
Leaves by night and flowers by day.

Leaves and bark, leaves and bark,
To lean against and hear in the dark.
Petals I may have once pursued
Leaves are all my darker mood

- Robert Frost