Spanish moss vs love-in-a-mist

Spanish moss

noun
  • A gray epiphyte that hangs down from trees, Tillandsia usneoides, native to the southeastern US and throughout humid tropical and subtropical parts of the Americas. 

love-in-a-mist

noun
  • Nigella damascena, an annual flowering plant of the genus Nigella, the blooms of which are generally blue in colour, though also found in shades of pink, white or pale purple. 

How often have the words Spanish moss and love-in-a-mist occurred in a corpus of books? (source: Google Ngram Viewer )