Hottentot fig vs icicle plant

Hottentot fig

noun
  • The acidic edible fruit of this plant. 

  • Carpobrotus edulis, a South African plant. 

icicle plant

noun
  • A plant in the daisy family,Asteraceae, with long, powdery-white leaves (Helichrysum thianschanicum). 

How often have the words Hottentot fig and icicle plant occurred in a corpus of books? (source: Google Ngram Viewer )