Why to name green with blue ?

There are some cultures which have strange identification. To name a green color with blue or vice versa.
For example,
- in Japan they say 'blue light' for green light at the traffic light. It may the same case for Korea.
- in Aceh they say 'blue leaf' for green leaf on the tree.
- Sumatra Barat and Riau they frequently interchange the green and the blue
- Minhasa they call the green little chilli with 'blue chilli'.

Can someone confirm this and why ?

Tags: blue, green, interchange, color
Tags: Indonesia