During the Dark Ages, the fern seed was believed to render men invisible. In medieval England, the root of the common male fern was an important ingredient in love potions, as demonstrated in this ancient Gaelic song:
"Twas the maiden's matchless beauty
That drew my heart anigh,
Not the fern-root potion,
But the glance of her blue eye."
The fern generally signifies sincerity, confidence, and shelter. A royal fern denotes reverie, while the exchange of a maidenhair fern expresses a secret bond of love.