Hardenbergia violacea is widespread along the coast and adjacent ranges in the eastern and southern states on the mainland. In Queensland it grows south from the coastal region of Mackay and the inland areas of Pentland and the Blackdown Tablelands . It grows in coastal heath and forest and inland, often among boulders, in drier eucalypt forests. It is classed as endangered in Tasmania, as it is only known from two natural populations, on private land . There is no variation recorded for this species but given its wide distribution, its growth responses are likely to vary with changes in climate and other environmental factors.
Flowering and seeds
There are records of spring flowering of Hardenbergia violacea in northern populations [26, 43] and a more extended flowering period over winter-spring in southern populations . Fruiting pods are ripe in summer. Seeds have an elaiosome (a sugary food source attached to the seed) and are dispersed by ants . The seeds will easily germinate after scarification of the seed coat by chipping and sowing at an optimum temperature of 20 degrees . Seeds can be placed in hot water then cooled down as a pre-treatment, though boiling water should be avoided with this species .
Cultivation and uses
The popularity of this species as a garden ornamental has led to a multiple of variants, with purple, blue and white flowers and vigorous scrambling or more clumping shrubby plant habit. The boiled leaves have been used as a beverage .
Mean annual rainfall: 400-2400 mm
Rainfall distribution pattern: summer, uniform or winter
Frosts (approx. no. per year): greater than 20
Frost intensity: light to moderate (0 to -5°C)
Mean annual temperature: 10-21 °C
Mean max. temperature of the hottest month: 21-33 °C
Mean min. temperature of the coldest month: -3-13 °C
Altitude: 0-1250 metres
Tolerance of extremes in climate
Drought: known to be moderately drought tolerant
Frost: tolerates frosts in the 0° to -5°C range
Texture: clay loam or loam, sandy loam, sandy clay loam
Soil pH reaction: acidic (less than 6.5)
Soil depth: skeletal to shallow (less than 30 cm)
Tolerance of adverse soils
Soil waterlogging tolerance: nil - sensitive to waterlogged soils
Biological traits under cultivation
Habit: evergreen vine
Longevity: short-lived less than 15 years
Growth rate: fast
Root system: shallow and spreading
Shade tolerance: grows best in full sunlight or tolerates partial shade
 Carr D (1997) Plants in Your Pants: a pocket guide for the identification and use of the common plants of the northwest slopes. Greening Australia NSW, Armidale.
 Leber BA (1977) Wildflowers of south-eastern Queensland, Volume 1. Botany Branch, Department of Primary Industries, Brisbane.
 National Herbarium of New South Wales (2008) PlantNET - Flora of New South Wales. (Online http://plantnet.rbgsyd.nsw.gov.au/floraonline.htm Accessed: February 2008)
 State Herbarium of South Australia (2007) Electronic Flora of South Australia: flora fact sheets. (Online http://www.flora.sa.gov.au/factsheets.html Accessed: February 2008)
 Lazarus E, Lawrence N, Potts W (2003) Threatened Flora of Tasmania. Threatened Species Unit DPIWE, Tasmania. (Online http://www.dpiw.tas.gov.au/ThreatenedFloraCD/ Accessed: September 2007).
 Flynn S, Turner RM, Dickie JB (2004) Seed Information Database (Release 7.0, October 2006). (Online http://www.kew.org/data/sid/ Accessed: July 2007).
 Bonney N (2003) What Seed Is That? A guide to the identification, collection, germination and establishment of native plant species for central southern Australian landscapes. Neville Bonney, Tantanoola.
Australian Plants Society – South Australia: http://www.australianplantssa.asn.au/hardenbergia.html
Australian Society Growing Australian Plants: http://asgap.org.au/h-viol.html
Gardening Australia ABC Television – Hardenbergia: http://www.abc.net.au/gardening/stories/s1460240.htm
PlantNet NSW Flora Online – species description & distribution: http://plantnet.rbgsyd.nsw.gov.au/cgi-bin/NSWfl.pl?page=nswfl&lvl=sp&name=Hardenbergia~violacea
South Australia Flora Online – species description & distribution: http://www.flora.sa.gov.au/cgi-bin/texhtml.cgi?form=speciesfacts&family=Leguminosae&genus=Hardenbergia&species=violacea
Threatened Flora of Tasmania: http://www.dpiw.tas.gov.au/ThreatenedFloraCD/Hardenbergia%20violacea.pdf