helianthus vs sunbloom

helianthus

noun
  • Any plant, of the genus Helianthus, having large flower heads with dark disk florets and showy yellow rays; the sunflowers 

sunbloom

noun
  • Any bloom or flower which resembles the sun or emerges in the sun. 

  • Synonym of sunflower 

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