Melaleuca irbyana, Swamp Tea Tree, develops into a large shrub or small tree in the wild. In our cold climate garden plants only reach a height of about one metre. Plants, in another local garden, have grown into a similar size.
Melaleuca irbyana grows in open eucalypt forests on poorly drained sites. Our plants are probably restricted in size because they are growing in well drained, rather dry sites.
The bark is spongy and papery. Branches are pendulous with small leaves with taper to a point and are pressed against the branches. Flowers are white, scented and held in terminal spikes up to 2.5 centimetres long. Each spike is composed of 3-12 individual flowers. Flowers appear from September to January. Small, woody fruits are flattened spheres. Seeds are released when they mature.
Melaleuca irbyana is classified as a threatened species in both NSW and Queensland.
In our garden plants are grown as foreground specimens in garden beds. Growth habit, foliage and flowers are all attractive features. Tip pruning helps to shpae plants and make foliage much more dense. They grow naturally in heavier (clay-based) or alluvial to sandstone, poorly-drained soils and so may need this requirement to do well. They likley benefit from additional water in dry times.
May be hard to source as it is a threatened species. Check with local native nurseries. It is sold at at least one nursery in NSW (see references).
Propagate from seed and cuttings.
The species was previously known as M. tamariscina subsp. irbyana. M. tamariscina is found in central Queensland.
Fire response unknown. May be able to regenerate from epicormic shoots and suckering or through the seed bank.
Melaleuca – is derived from the Ancient Greek mélas (μέλας) meaning “dark” or “black” and leukós (λευκός) meaning “white”, apparently because one of the first specimens described had fire-blackened white bark.
irbyana – named for L. G. Irby (1883-1964), a Museum Collector who collected the type specimen.
This species is threatened with extinction at the State level with the category of Endangered.
NSW Flora Online (PlantNET) – Melaleuca irbyana profile page https://plantnet.rbgsyd.nsw.gov.au/cgi-bin/NSWfl.pl?page=nswfl&lvl=sp&name=Melaleuca~irbyana
NSW Office of Environment and Heritage – Threatened species profiles – Melaleuca irbyana https://www.environment.nsw.gov.au/threatenedspeciesapp/profile.aspx?id=10518
Burringbar Rainforest Nursery – Melaleuca irbyana sales page https://burringbarrainforestnursery.com.au/plant-search/melaleuca-irbyana-swamp-tea-tree/