Tree
Shoestring Acacia
Acacia stenophylla · Fabaceae
Also called: River Cooba, Eumong, Dalby Myall
Shoestring Acacia (Acacia stenophylla) is a low-water tree well suited to Tucson and the low desert. It grows to 20-30 ft H x 15-20 ft W in full sun, with a moderate to fast growth rate.
Shoestring Acacia at a glance
- Water use
- Low (established)
- Sun
- Full sun
- Mature size
- 20-30 ft H x 15-20 ft W
- Growth rate
- Moderate to fast
- Bloom
- Creamy white to pale yellow (puffball flowers), Late fall through winter into early spring
- Cold hardiness
- Hardy to about 15-20 F; USDA zones 9-11
- Soil
- Adaptable to most well-drained desert soils including caliche and clay; tolerates some salinity. Needs good drainage.
- Native range
- Australia (inland watercourses)
- Best used as
- Shade tree, Vertical accent / specimen, Screen, Streetscape tree
- Wildlife
- Pollen and nectar attract bees and other pollinators; provides bird cover. Long bead-like seed pods are ornamental.
- Toxicity
- No significant toxicity reported for landscape use.
How to grow Shoestring Acacia in Tucson & the low desert
Watering
Deep, infrequent irrigation once established; water deeply every 2-3 weeks in summer and monthly or less in winter. Established trees are notably drought tolerant.
Fertilizer & nutrients
Little to no fertilizer needed; nitrogen-fixing legume. A light spring feeding may aid establishment of young trees only.
Pruning & care
Prune in late spring or summer to establish a strong central leader and well-spaced scaffolds; thin to reduce wind load. Stake young trees as the weeping habit can make them floppy when young.
Notes
Distinctive long (to ~16 in), narrow, pendulous phyllodes give a graceful weeping silhouette. More wind-firm and longer-lived than willow acacia, with a narrower footprint suited to tighter spaces. Produces constricted 'string of beads' seed pods. Can reseed modestly. Evergreen.
Sources: AMWUA 'Landscape Plants for the Arizona Desert'; University of Arizona Cooperative Extension; Arizona-Sonora Desert Museum; Arid Zone Trees grower references