Myrtle-leaf milkwort (Polygala myrtifolia) has been widely cultivated as a garden ornamental, particularly in the temperate regions of Australia. The typical form of the species is generally no longer cultivated, but a modern cultivar (i.e. Polygala myrtifolia 'Grandiflora') is now widespread in cultivation. This cultivar was thought to be sterile, but it has recently been found to set some seed.

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Widely naturalised in the coastal districts of southern Australia (i.e. in the coastal districts of eastern New South Wales, Victoria, Tasmania, southern South Australia and south-western Western Australia). Less common in the sub-coastal and inland regions of Victoria, South Australia and south-western Western Australia. Also naturalised on Norfolk Island.

Naturalised overseas in New Zealand and south-western USA (i.e. California).
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