Indian corn vs sweet corn

Indian corn

noun
  • a variety of maize in which the kernels are variously coloured, rather than being all of the same colour 

  • a variety of candy corn that contains chocolate in addition to honey-based candy 

sweet corn

noun
  • Corn (specifically maize) suitable for eating by humans, as distinguished from corn raised as animal feed. 

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