Knifeleaf Acacia Acacia cultriformis Knife Leaf Wattle, Wattle Leaf, Wattle Form: Irregular shrub; with age a rounded small tree or mounded shrub Seasonality: Evergreen Size: 6-12 feet, spread 6-15 fetet; in Tucson, typically only to 8ft with equal spread Leaves: Unusual triangular shape, like knife blade or shark fin; no petiole (phyllodium); rough texture, off-green Flowers: On terminal end of each branch, cluster of small golden yellow puffballs; bloom in early to mid spring Fruit: Small slender pod; 1.5-2 inches long, 1/2 to 1/4 inches wide Stems/Trunks: May form slender trunk with age Range/Origin: Arid regions of eastern Australia USDA Zones: 5b-11 Exposure: Full sun, part shade Water: Little once established; once per week or per every two weeks Soil: Adaptable, to most soil types. Proper amending with compost or other soils additives will give best results. Propagation: Seed, easily grown from seed; 95% success rate. Cuttings provide a 60% success rate. Maintenance: Low, best when left with natural form; prune to shape if desired Growth Habits: Evergreen tree or shrub, 10 feet to 16 feet tall (3 m-4.8 meters), 10 feet to 15 feet in spread (3 - 4.5 meters), grayish green, leaves Known Hazards: None known Cultivation Details: Prefers a sandy loam and a very sunny position. Succeeds in dry soils. Succeeds in any good garden soil that is not excessively limey. Most species become chlorotic on limey soils. This species is probably very tender in Britain, but it has been grown outdoors in the mildest parts of Cornwall. Closely related to A. pravissima. This species has a symbiotic relationship with certain soil bacteria, these bacteria form nodules on the roots and fix atmospheric nitrogen. Some of this nitrogen is utilized by the growing plant but some can also be used by other plants growing nearby. Propagation Notes: Seed - best sown as soon as it is ripe in a sunny position in a warm greenhouse. Stored seed should be scarified, pre-soaked for 12 hours in warm water and then sown in a warm greenhouse in March. Germinates in 3 - 4 weeks at 25
