Here’s what I think I know about growing ulu (aka breadfruit)…

Hawaiian variety is very good. Start there. Get them from gulches. Second small gulch in upper Laupahoehoe. Cut rhizome on the tree side. Air layer, then come back in a few weeks and check on it.
– It likes gulches
– doesn’t like the wind
– happy in elevations up to 1500 feet
– they grow big. Need to prune them regularly at 10 feet. to keep them producing. Side branches are encouraged so you can pick them at 10 feet. 
– trees planted 40 ft apart 
– early canoes were made from ulu
– ulu fiti is a great variety
– Grow from cutting from roots and airlayering branches
– plant companion trees of Chinese plums and Mac nut to protect it. 
– Puna has some good stock, but need to have it in a pot the first year or two. Also Kukaiau, Paauilo Mauka 
– create a rock wall about 8-9 foot radius around, starts smaller and extends as the tree grows

My Elevation: 1000 feet

My Water: 100 inches per year

My Soil: pH=neutral, N=low, P=neutral, K=neutral

My luck growing it (as of July 2019): good. tried 1 tree from Plant It Hawaii 4/12/2019. Some brown leaves after transplant but seems to keep growing