Acacia pruinosa, the Frosty Wattle, is a medium to tall shrub.
The Frosty Wattle is found in northern NSW, on the north western slopes and northern tablelands, in a moderately narrow corridor from Tamworth to border, continuing into Queensland in a patchy distribution to the west of Warwick and Toowoomba, as far north as Tara.
It grows in dry sclerophyll woodland and forest on granite.
Australian Wattles at least, can be broadly placed into 1 of 3 recognisable groups:
This species belongs to Group 3.
The leaves are bipinnate, to 15 cm long and 15 cm across, with 9-20 pairs of pinnules (leaflets) per compound leaf, The pinnules are grey-blue and up to 20 mm long by 5 mm wide.
Globular flower heads are produced to 10 mm in diametre, amazingly carrying from 40-60 very small staminate and deep yellow flowers. The heads are grouped in long racemes or panicles of up to 20, in leaf axils, occurring between August and November.
The pods, that follow the flowers, are up to 14 centimetres long, leathery and constricted between seeds. They ripen between November and January. This is the normal seed ripening period for all spring flowering wattles.
Acacia pruinosa is one of the few wattles that does not take kindly to pruning. Plants may become straggly and is best grown as a component of native shrubberies.
Not too much information is currently available regarding its cultivation. However, it may be able to be grown reliably if plants can be sourced. It grows on granite soils mainly in the wild and may need similar conditions to thrive in a garden. Grow in full sun for best results.
Propagate from seed that should be soaked in boiling water before sowing.
The species was previously known as A. spectabilis var stuartii.
The type was collected by Alan Cunningham on the Liverpool Plains, NSW in 1827.
Most wattles will die in a fire and regenerate from seed. Some species exhibit suckering from basal parts and roots.
Acacia is a highly diverse genus, with over 1500 recognised species (placing it in the top-10 most-diverse plant genera) occurring in most continents except for Europe. Australia has about 970 spp., most of which are endemic. There are also about 10 exotic species. NSW has about 235 recognised species. Some species have become weeds in other states outside of their natural range (e.g., wattles from Western Australia into NSW and vice versa).
Acacia – from Greek Akakia – which refers to an Ancient Greek preparation made from one of the many species; the name of which derives from akis, meaning “thorn” – referring to the thorns of species in Africa.
pruinosa – Latin meaning “frosty” – basically referring to the powdery-waxy coating on the stems and branchlets (pruinose).
This species is not considered to be at risk of extinction in the wild.
NSW Flora Online (PlantNET) – Acacia pruinosa profile page https://plantnet.rbgsyd.nsw.gov.au/cgi-bin/NSWfl.pl?page=nswfl&lvl=sp&name=Acacia~pruinosa
Wattle – Acacias of Australia – Acacia pruinosa profile page https://apps.lucidcentral.org/wattle/text/entities/acacia_pruinosa.htm