Warning over 'pretty' flower invading Aussie gardens: 'They're everywhere'

By removing invasive plants from your home and region could become more sustainable places to live, gardener Steven told Yahoo.

A plant popular with Aussie homeowners for its low maintenance and tall clusters of colourful bell-shaped flowers may actually be harming the environment by invading gardens, native bushland and roadside areas.

Agapanthus, a South African perennial otherwise called an African lily or lily of the Nile, has become incredibly prominent across Australia since its six species were presumably introduced as garden ornaments in the 1970s. Although referred to as an environmental weed, Agapanthus, which can be found in NSW, Victoria, Tasmania, South Australia and WA, are poisonous and can spread quickly, eliminating habitat for native fauna.

Left, an Agapanthus plant's invasive root system. Right, Steven the gardener holding a spent Agapanthus flower head. Source: TikTok/@Zanisgardening
Agapanthus plants have been a popular feature in Aussie garden beds and roadside areas for decades, but they are 'so invasive', Steven says. Source: TikTok/@Zanisgardening

In a TikTok video posted this week, Steven from Zani’s Gardening — a horticulture blog based on Melbourne’s Mornington Peninsula — described them as “so invasive to the Mornington Peninsula and the Dandenong Ranges” outside of Melbourne.

“As you can see Agapanthus can spread out and clump up really easily,” he said while pointing to spent flowers on one of many bushes seen on a nature strip off a busy road. “Now they spread when the pretty flower that a lot of people like seeds and self reproduces. They can often reproduce through roots on the ground and just completely take over an area.”

Removing invasive plants creates sustainable cities

Steven, who has worked at nurseries since he was a teenager, told Yahoo News that by encouraging people to remove invasive plants from their homes and replace them with natives, cities will become more sustainable places to live.

“More native plants attract more bees and birds to their natural environment,” he explained. “A good garden should include a few natives as part of the design to accommodate for this. Also keep in mind the growth habits of other plants … you want to read the label and have a good understanding that what you purchase will suit the fauna/birds and not grow [big enough] to destroy and take over a certain area.”

Steven said the move could also have a positive impact on prospective property value. “A property likely won’t sell as well if they have invasive plants that will cost a lot to remove,” he said.

Agapanthus in a garden in Australia.
'Deadheading' an Agapanthus plant's spent flowers just before they develop into seeds can help stop it from spreading so much. Source: AAP

To remove an Agapanthus, the gardener said the best option is to spray it — a popular option is glyphosate — until it “breaks down naturally”. “You’ll have a much better chance of actually getting them out … the roots are really vigorous and they go quite deep into the ground so to shovel them out can be quite difficult,” Steven said.

Council urges residents to bin Agapanthus seeds

Last month, Wingecarribee Shire Council in the Southern Highlands of NSW urged residents to appropriately dispose of Agapanthus seeds by “deadheading” — removing the spent flower heads just before they develop into seeds — ideally between December and March.

However, the cuttings cannot simply be placed in a green compost bin. “Agapanthus seeds are incredibly persistent, resilient, and they can survive in soil for years, even in mulch piles,” General Manager of Wingecarribee Shire Council Lisa Miscamble warned.

They should be placed in the green garden organics bin to ensure they’re properly decomposed and won’t spread any further, the council said.

Love Australia's weird and wonderful environment? Get our new newsletter showcasing the week’s best stories.