A shrub growing to about 2 metres high.
It occurs from the Heathcote and Mittagong districts in New South Wales, extending down the coast and coastal inland, to East Gippsland in Victoria.
It grows in creek beds and on the banks of streams in dry sclerophyll woodland forests.
Callistemon spp. have simple and alternate to spiral leaves. In this species, leaves densely arranged, linear, subulate or terete, to 40 mm long, and 3 mm wide, with a short mucro.
In Callistemon species, flowers are usually arranged in spikes (the “bottlebrush”) which are produced at the terminals but which the stem then grows past, into a leafy shoot. Flowers have five small circular sepals and five circular petals which persist on the flowers. Like many other Myrtaceae genera, the flowers are conspicuously staminate with each flower having many stamens surrounding one carpel. The stamens are typically free although may be fused at the basal parts (a generally useful identifying feature for the genus to distinguish it from Melaleuca). The pedicels of the flowers are very short. In this species, In this species, inflorescences are to 8 cm long, and 4 cm diam., mostly leafy with filaments dark crimson.
Capsules are to 5 mm diameter, arranged in the same spike-like structure along branches.
C. subulata is commonly cultivated because of it abundant and attractive flowers in spring and summer. It is hardy but benefits from the application of low-phosphorus fertiliser. It can be used as a groundcover-shrub and flowers prolifically – making it highly desirable.
Flowers attract birds and bees.
This author is not aware of any pests.
A low-phosphorous fertiliser should be applied in spring and autumn and light vegetative mulch will help retain soil moisture and reduce weed growth.
Tip pruning can be undertaken almost anytime that the flowers are not developing and this helps the plant to produce new shoots. The best type of pruning is to cut off 2/3s of the new flowers as soon as the flower is spent. This forces many new shoots that will produce next seasons flowers.
I planted some of these plants about 12 years ago in a garden, in the northern Sydney suburb of Westleigh and they have all grown to about 1.2 metres high. They are still growing well, even though the soil is now much drier and they only receive dappled morning light and some full late afternoon sun.
From seed or cuttings. Can regenerate from seedbank after fire. Many bottlebrushes also exhibit reshooting from branches and basal parts of stems/trunks after fire or pruning.
There is at least one cultivar of this species called ‘Brogo Overflow’ (see references below).
The genus Callistemon has been subject to recent taxonomic revision with early and recent botanists including Ferdinand von Mueller and Lyndley Craven (deceased in 2014) proposing to ‘lump’ the genus into Melaleuca and others. Craven et al. (2014) published new species combinations which included the renaming of all Callistemon species to Melaleuca, based on evolutionary relationships and DNA evidence and other features.
Currently, the NSW Herbarium advises that the Callistemon genus can still be used. There are currently about 30 species of Callistemon, which are found in all states of Australia as well as New Caledonia. About 28 are endemic to Australia. NSW currently recognises 24 species. New species have been described in the last 20 years.
Regenerates after fire from epicormic and basal shoots as well as from the seedbank.
Callistemon – From the Ancient Greek – Callos (κάλλος) – meaning “beautiful” (which is changed to κάλλη to describe a noun) and and stêma (στῆμα) meaning “stamen”, referring to the very showy staminate flowers of the bottle-brush inflorescences.
subulatus – is Latin for subulate – a long tapering triangular shape.
This species is not known to be at risk of extinction in the wild.
NSW Flora Online – Callistemon subulatus profile page http://plantnet.rbgsyd.nsw.gov.au/cgi-bin/NSWfl.pl?page=nswfl&lvl=sp&name=Callistemon~subulatus
Wikipedia – Melaleuca subulata profile page
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 – Callistemon subulatus ‘Brogo Overflow’ profile page https://www.gardeningwithangus.com.au/callistemon-subulatus-brogo-overflow-bottlebrush/