Heather is of Scottish origin, derived from the Old English 'hǽþer', which refers to the heath plant. It gained popularity in the late 19th century and was a Top 1000 name for girls born in the United States throughout much of the 20th century.
"Interestingly, the name Heather saw its peak popularity between 1969 and 1986, with over 70 births each year during this period. However, by 2007, the number of babies named Heather had significantly declined to just 5."