orchid vs petunia

orchid

adj
  • having a light purple colour. 

noun
  • A light bluish-red, violet-red or purple colour. 

  • A plant of the orchid family (Orchidaceae), bearing unusually-shaped flowers of beautiful colours. 

petunia

adj
  • Of a dark purple colour, like that of some petunia flowers. 

noun
  • Any of the flowering plants of genus Petunia, of which most garden varieties are hybrids. 

  • a homosexual 

  • A dark purple colour, like that of some petunia flowers. 

How often have the words orchid and petunia occurred in a corpus of books? (source: Google Ngram Viewer )