A fascinating variety, Acacia cultriformis can be used as a ground cover plant (prostrate form), small shrub or, if you can find it, the cascading form, sold as a grafted standard.
With a natural weeping habit, this is an Acacia with dense growth, masses of foliage, and golden balls of flowers from winter through spring.
Grow the prostrate form along the top of a retaining wall and let it naturally hang over the edge. You will have a green curtain of foliage year-round and a yellow curtain when in flower.
The grafted standard form makes a great feature plant.
How to Grow Knife-Leaf Wattle
If you are growing the standard form, it will be grafted. As with most grafted plants, you need to stake the plant until the stem or trunk strengthens enough to support the head.
A slow-release Native Plant fertiliser will be adequate in most soils once a year.
Acacia cognata ‘Waterfall’ is another cascading Acacia grown as a weeping standard.
- Botanical name – Acacia cultriformis
- Common names – Knife-Leaf Wattle or Cascading Wattle
- Soil – Well-drained, humus-rich
- Position – Full sun to a little afternoon shade
- Foliage – Deep silvery green and triangular in form
- Flowers – Small balls of yellow flowers
- Flowering time – Spring to summer
- Growth rate – Fast to medium
- Frost tolerant – yes
- Drought tolerant – yes
- Pruning – Grafted varieties (standards) will need to have all growth below the graft removed regularly.