Isaac Olson 
Paul Rosser’s weed warning in April named the garden escapes that keep turning up around the southern vales: gazanias, English ivy, cotoneasters. Pulling them out is the first job. The second job is the one that gets forgotten, and it decides whether you do the first job again next year.
Bare ground does not stay bare. Cleared soil is seed bed, and the seed already in it is mostly the weed you just removed. The way to hold the ground is to fill it quickly with something you want, mulch between the plants, and keep the gaps closed until the new planting knits together.
The replacements are easy to find, because every escape on the list has a well behaved local equivalent that does the same job.
Where gazanias ran along a sunny verge or bank, the native daisies take over. Cut leaf daisy and yellow buttons flower for months on no water once established, and fan flower spreads into a mat the way gazania does without the seed that travels.
Where ivy covered a fence or smothered a slope, creeping boobialla will cover ground in a season, and native violet fills the shady corners. For a fence, a native climber such as happy wanderer does the screening without rooting into every wall it touches.
Where cotoneaster was planted for its berries, the birds that spread it will take correa, bottlebrush and coastal rosemary instead, and those plants feed honeyeaters through the Fleurieu winter rather than the starlings.
Plant in autumn or early winter if you can, so the roots are down before the dry summer, and choose plants raised for Adelaide’s wet winters and hot summers rather than for the eastern seaboard. South Australian orders at our nursery last year were the least native of any state, at 12 per cent, so there is room to move.
A longer guide to garden escapes, why they spread and what to put in their place is at nurserynearme.com.au/blogs/blog/how-invasive-plant-species-affect-ecosystems, and a list of plants that suit Adelaide gardens is at nurserynearme.com.au/blogs/blog/best-plants-for-adelaide-gardens
Isaac Olson is a director of Nursery Near Me, an Australian online nursery that delivers to every mainland state.
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