`Ohi`a is a variable species, hence the species name, polymorpha meaning many forms. 'Ohi'a can be a tree or shrub or anything in between; a lot depends on where the seed came from. The blossoms may be red, orange, or yellow and the foliage may range from a waxy green to a fuzzy gray with reddish new growth called 'liko'.
`Ohi`a does best in mesic or wet environments and requires moderate water. It grows well at lower elevations with regular watering. Full sun is good for more flowering and growth in general. The variability of this species offers potential for a hedge, specimen planting or a mixed windbreak so be careful when purchasing an `Ohi`a to ensure the form you are looking for. 'Ohi'a have many surface roots so newly planted trees benefit from fertile soil in a large area around the main trunk.
Insect pests include rose beetle and may defoliate young plants, but they will soon grow out of it. Don't let ants host scale or aphids. `Ohi`a is one of the main canopy trees of the wet Hawaiian forest and also a pioneer species. There are other species of Metrosideros native throughout New Zealand and Australia.