How Mistletoe Became a Christmas Kissing Tradition

The yuletide decorations are up: a trimmed tree, jolly stockings on the mantel and—wait, what’s that white-berried weed hanging from the ceiling? And why are people so amorous when they find themselves beneath it? 

Mistletoe, a parasitic plant, is actually accustomed to the suspension: In nature, it grows only on other trees’ branches. And it’s long been associated with mystical power: In Norse myth, the god Balder is mistakenly killed by an arrow of mistletoe—after which the plant becomes synonymous with his grieving mother’s undying love. While mistletoe’s berries are poisonous, ancient Romans and Greeks used its leaves medicinally, to treat cramps, epilepsy and ulcers. And first-century Celtic druids apparently used mistletoe to make a sacred fertility elixir—one historic use that presaged the plant’s now-dominant identity as an excuse for kissing.

The first known reference to smooching under the plant dates to a 1784 English poem, in which three men “kiss beneath the mistletoe” the lips of a “girl not turn’d of twenty.” By then, any woman or girl who walked beneath this vegetal decor had to stop and wait to be kissed. One historian suggests the tradition was thought up by a “particularly lusty and inventive” British boy, whose trick spread around the country, then the world. As the American author Washington Irving wrote around 1820, each berry on a sprig of mistletoe had come to represent a kiss that a man was allowed to bestow upon a young woman standing underneath the plant, and “when the berries are all plucked the privilege ceases.” As for the girl on the receiving end, the era’s (otherwise chaste) social customs dictated she never refuse a kiss under the mistletoe, lest she invite bad luck on the marriage market.

Today’s typical mistletoe decor differs from its 19th-century precedent in a few ways. Its berries aren’t poisonous—because the stuff’s usually fake; those false berries are often mistakenly red, rather than white; and the sprigs are (one hopes) no longer being used to force kisses upon unwilling recipients. Still, at family gatherings and in cheesy movies, mistletoe remains the catalyst of many an awkward or playful holiday peck.