cherry laurel vs philadelphus

cherry laurel

noun
  • Prunus laurocerasus, an evergreen shrub, native to regions bordering the Black Sea in southwestern Asia. 

  • Prunus caroliniana, native to the southeastern United States. 

philadelphus

noun
  • Any of the genus Philadelphus of shrubs. 

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