A shrub that will reach a height of potentially 5 metres with a spread to possibly 2 metres. It is often seen in the field to 2 metres tall by less than 1 metre wide.
It is a very commonly seen species in many habitats, with a large natural geographic range in NSW, gorwing along the entirety of the coast and tablelands areas, as well as the north and central western plains, extending just into the far western plains. It has been recorded in the far north-east corner of Victoria. It extends into Queensland, growing as far north as around Bundaberg and west of here towards Tambo.
It is often found in wet and dry sclerophyll woodland and forest as well as rainforest edges and shrubland, on a variety of soils but often heavier, i.e. clays, alluvium and volcanic.
Ozothamnus spp. have simple and alternate/clustered leaves. In this species, they are dark to mid green, linear to narrowly-elliptic, to about 15 mm long by 2 mm wide, with margins strongly curled under and with the lower surface covered in white woolly hairs. Leaves are somewhat aromatic and rough to the touch due to short hairs on the upper surface.
Ozothamnus are in the daisy family (the world’s largest family of species) which means their flowers are arranged in a capitulum or ‘daisy head’. Daisies are somewhat unique in that they have evolved inflorescences that appear to look like one flower. The Sunflower (*Helianthus annuus) could be considered the most grandiose example. The capitulum consists of:
In some daisies, a range of variations are thrown up such as an absence of ray florets; purely male or female disc florets; and some discs having an involucre of bracts rather than ray florets. A sunflower would have hundreds of disc florets in the centre, surrounded by its larger petal-like yellow ray-florets.
In Ozothamnus spp., the capitula are arranged in tight terminal corymbs or clusters. The capitula (or heads) themselves have an overall globose to oblong or campanulate shape. There are no ray florets. Instead, there are tiny disc florets surrounded by an involucre – a whorled overlapping arrangement of papery bracts. The florets are mainly bisexual with a few female-only.
In this species, the corymbs can be up to 7 to 8 cm across by 5 cm long. Each capitulum is about 3 mm by 3 mm wide. Overall, the papery bracts provide most of the colour and are mostly white but can be pink, appearing in winter and spring. Even though individual capitula are very small, they can be produced profusely in many corymbs, creating a nice display. Each capitula starts off as globose structures in bud, and then open wide and appear as a very small daisy.
The fruit of Ozothamnus (and many daisies) is an achene – a small fruit with one seed surrounded by a very thin outer wall and with a ring (pappus) of bristles attached which aids wind dispersal. Ozothamnus have four-angled achenes, usually only a few millimetres long.
This species is known to be cultivated and can be grown very readily. It is commonly sold at native and mainstream nurseries. It is also used commonly in bushland regeneration projects.
The species is widely grown for the cut flower trade and a number of cultivars have been developed. One cultivar is ‘Royal Flush’ that has purplish buds opening to pink flowers. Other cultivars include ‘Pink’, ‘Coral Flush’ and ‘Radiance’.
This species is best grown in full sun position, on a heavier soil – with some clay or alluvium but may also tolerate sandy-enriched soils. Ensure good drainage.
Ozothamnus diosmifolius tends to become rather straggly so pruning is necessary after flowers fade.
Being a daisy-species, it may be short lived. (This Editor grew a plant in a western Sydney garden, years ago, and it grew to 4 metres tall with multiple stems, and died after about 10 years).
A useful plant to attract a wider range of insects to the garden and provide more variety of flower shape and colour.
Propagate from seed and cuttings. Any cultivars must be propagated by cuttings to maintain ‘true-to-type’ forms.
Ozothamnus diosmifolius was previously known as Helichrysum diosmifolius and is known variously as Sago Flower and Rice Flower. Both names probably refer to the shape and/or appearance of the flower buds.
The species is cultivated in California.
Most Ozothamnus species would regenerate from seed after fire.
Ozothamnus is a genus of about 53 species, occurring in Australia, New Zealand and New Caledonia. About 44 species are endemic to Australia, occurring in all the eastern states and South Australia. NSW currently has about 24 species.
Ozothamnus – Greek – Ozo (ὄζω) – translating to ‘stink’ or ‘smell’ and –thamnos (θάμνος) – meaning ‘shrub’ – capturing the strong odour of many species.
diosmifolius – Latin – Diosma – a genus of plants in the Rutaceae family, native to South Africa and -folia, meaning ‘leaves’ – capturing the similarity of this species to those of Diosma.
This species is not considered to be at risk of extinction in the wild.
NSW Flora Online (PlantNET) – Ozothamnus diosmifolius profile page https://plantnet.rbgsyd.nsw.gov.au/cgi-bin/NSWfl.pl?page=nswfl&lvl=sp&name=Ozothamnus~diosmifolius
Australian Native Plants Society Australia – Ozothamnus diosmifolius profile page https://anpsa.org.au/plant_profiles/ozothamnus-diosmifolius/
Wrigley, J.W. & Fagg, M.I. (2001). Australian Native Plants – Propagation, cultivation and use in landscaping. 4th edition. New Holland Publishers, Pty. Ltd. Australia.
Gardening with Angus – Ozothamnus diosmifolius ‘Radiance’ profile page https://www.gardeningwithangus.com.au/ozothamnus-diosmifolius-radiance-rice-flower/