'Ohi'a Lehua (Metrosideros polymorpha)

Flowers that only flourish at high elevations.

This is a huge money maker for the islands and it is cultivated by making hybrids of the different species. It grows at high elevations which makes it difficult to grow. This flower is popular for flower arrangements and was one of the first plants to colonize lava flow areas. 

Picture taken from: www.wildlifehawaii.com