Blackberry winter

Blackberry winter is a colloquial expression used in south, midwest North America; as well as in Europe, Sinosphere Vietnam and East Asia, referring to a cold snap that often occurs in late spring when the blackberries are in bloom. Other colloquial names for spring cold snaps include "dogwood winter," "whippoorwill winter," "locust winter," and "redbud winter." The different names are based on what is blooming in particular regions during the typical spring cold snaps. Another colloquialism for these spring cold snaps is "linsey-woolsey britches winter," referring to a type of winter long underwear which could be put away after the last cold snap. The blackberry winter term may have arisen to describe the belief that a spring cold snap helps the blackberry canes to start growing.

In East Asia and Vietnam, the blackberry winter is known as Miss Ban's Winter (, , ), as it associated with an ancient folk tale of Miss Ban, a young daughter of the Jade Emperor who is hard-working but clumsy. She marries a husband, who is also a god, with the hope that she could improve her housework skills. In the winter, she dedicates herself to tailor clothes for her husband, but her clumsiness results in her being unable to finish the job until the end of winter. When she finishes, March has already gone by; thus she misses the winter. She falls down crying, and the Jade Emperor, touched by her will, decides to return the cold for a week to allow her husband to wear the clothes of Miss Ban. Thus, this is known as Miss Ban's Winter.

In rural England, the equivalent term is "blackthorn winter", so-called because the blackthorn in hedgerows blossoms in early April, preceding the leaves, and presents an intense white spray against the black branches of the bush. In Finland, where the phenomenon is incredibly common – even in the month of May – the expression to describe it "takatalvi" (lit: back winter; most likely from the word takaisin 'come back', as in "returning winter") is part of common parlance.