Once considered a form of "black magic", an army of predatory insects is being used to tackle pests in a popular century-old Sydney garden.
Centennial Park in the city's east was formerly a swamp that was turned into a drinking water source, before it was transformed into parklands and opened to the public on Australia Day in 1888.
About 20 years later, then-park director Joseph Maiden planted a rosarium, which in Latin means "rose garden".
Today, it is home to 33 different varieties of roses, with an estimated 800 plants overlooking Busbys Pond.
Geese are often seen walking among the floral bursts of colour, giving it a somewhat fairytale appearance.
Unfortunately, it is not just humans and birdlife that enjoy the sweet scents. Pests do too.
A team of ladybirds and parasitic wasps, led by Western Sydney Parklands senior horticulturalist Tristan Harman, have been tasked with managing "a fairly heavy aphid infestation".
Mr Harman said it was normal for new shoots to attract thousands of the bugs each year after the roses were pruned back in winter, but they had to be managed.
"They're pretty amazing survivors, like they pump out clones if they need to."
Aphids can cause roses to become distorted and puckered. The pest can also pass on viruses between plants.
