bleach vs grow dark

bleach

verb
  • To be whitened or lightened (by the sun, for example). 

  • To lose color due to stress-induced expulsion of symbiotic unicellular algae. 

  • To treat with bleach, especially so as to whiten (fabric, paper, etc.) or lighten (hair). 

  • To make meaningless; to divest of meaning; to make empty. 

noun
  • A variety of bleach. 

  • A chemical, such as sodium hypochlorite or hydrogen peroxide, or a preparation of such a chemical, used for disinfecting or whitening. 

  • A disease of the skin. 

  • An act of bleaching; exposure to the sun. 

grow dark

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