grass:

Who tended flowers, my girl, while you were playing

Some double game, or wearing out your glass.

They sleep—but what sweet things they have been

making,

By golden moons, to give you a surprise—

Beat slower, little hearts with wonder aching,

Keep in the dark yet, all you eager eyes!

The fairies sleep. But their high lord and master

Keeps wide-awake, and watches every hearth;