Three Chilly Saints
May 11, 12, and 13 are the feast days of Saints Mamertus, Pancras, and Gervais. These three are known as the Three Chilly Saints not because they were cold during their lifetimes, but because these days are traditionally the coldest of the month. English and French folklore (and later American) held that these days would bring a late frost. In Germany, they were called the Icemanner, or Icemen Days, and people believed it was never safe to plant until the Icemen were gone. Another bit of folklore claimed, "Who shears his sheep before St. Gervatius's Day loves more his wool than his sheep."