cat thyme vs valerian

cat thyme

noun
  • A low-growing herb, Teucrium marum, related to germander, which has a pungent scent that causes sneezing, but is attractive to cats. 

valerian

noun
  • A hardy perennial flowering plant, Valeriana officinalis, with heads of sweetly scented pink or white flowers. 

  • An extract of the dried roots of the Valeriana officinalis used in herbal medicine as a sedative. 

  • More generally, any plant of the genus Valeriana. 

  • The root of Valeriana officinalis, used in herbal medicine. 

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