And he said HE didn't do it--it was all the work of the pixies who lived in the woods across the brook.

There were more pixy babies than usual this spring, and the mothers were in a hurry for the cradles.

The tulips are the pixy babies' cradles, it seems.

The mother pixies come out of the woods at twilight and rock their tiny little brown babies to sleep in the tulip cups.

That is the reason why tulip blooms last so much longer than other blossoms.
The pixy babies must have a cradle until they are grown up.