Acacia koa

koa
Iconic Hawaiian acacia renowned for its grandiose form and glowing hardwood. Large landscape tree grows into a wide umbrella form.
height 30–60ft
width 15–35ft
tolerates Wind
water
needs
Low – Moderate
water
info
For the first three years after it’s planted, this acacia should be watered deeply but infrequently (when the top three inches of soil or so have dried). After that, will want deep irrigation every month or so during the dry season. Use drippers, emitters or a slow stream of water so that it doesn’t run off; allow the water to trickle all the way down through the deepest layers of soil.

A great trick for watering street trees is to drill a 1/8-inch hole on the bottom edge of a 5-gallon bucket, then set the bucket with the hole aligned next to the tree and fill the bucket with water. Fill once for a 1-5 gallon plant, fill twice for a 7-15 gallon plant, three times for 25g or larger plants.

Though these trees are drought tolerant, never let them go bone dry in a pot.
hardy
to
30F
exposure Part Shade – Full Sun
indoor
outdoor
Outdoor
drainage In Ground: Cactus Mix, In Pots: Cactus Mix, Tolerates Sandy Soil
fertilizing All Purpose, Low Needs
origin Hawaii, USA
california
native
No
sunset
zones
15–17, 20–24, H2

Sunset Zones Map

Outdoor Exposure Guide

OUTDOOR EXPOSURE GUIDE

Full Sun
Six or more hours of sun beams directly landing on the plant's leaves.

Part Shade
Three to five hours of sun beams directly landing on the plant's leaves.

Part Sun
One to two hours of sun beams directly landing on the plants leaves.

Full Shade
The plant is never fully lit by sun beams, but is in a bright spot or has dappled sunbeams playing over the leaves throughout the day.

Deep Shade
The plant never has dappled light on the leaves, and is in a place that feels dim, even on a nice sunny day.

SUNSET ZONES MAP

Growing Notes

Acacia are FAST growers. Acacia are also relatively short lived, typically growing for twenty to thirty years. At least with this tree, when it reaches the end of its life, you’ll have a nice collection of hardwood! Planting longer lived slower growing plants near your acacia giving them time to mature and give you a mature element when your tree is taken out.
Acacia do well in pots, which effectively “dwarf” them.
In some shade, acacia look softer and the colors come out more. They also tend to get more upright as they reach for the sun. This makes them a great choice for tight urban gardening.
This tree is forgiving of pruning. Choose to prune off lower branches for a standard tree form, or tip prune to create a dense shrub or screen. Typically wide acacia can be pruned into a narrower form.

Special Interest

Koa means bold, brave and fearless.