Fountain grass is the latest weed causing a problem around Adelaide’s suburbs. Here’s what you need to know and what you can do.

Fountain grass, a weed, growing in a garden bed beside a paved street
Fountain grass growing in a suburban street

Weeds have a huge impact. They steal space and water from native plants, are not as nutritious for local wildlife, impact on farming land and local food production, increase the intensity of fires, and rack up a huge cost in controlling them.

Adelaide’s milder than usual summer has allowed some weeds to take off, and we are keeping an extra close eye on Adelaide’s latest problem weed – fountain grass – to reduce its impact.

Discover more about this weed, why we need to control it, and how you can play a part in stopping its spread.

Close-up of the feathery pink-purple bristled seed heads (flowers) of fountain grass weed
The feathery pink-purple seed heads of fountain grass. Photo: Monica Seiler.

What is fountain grass?

Fountain grass (Cenchrus setaceous) is a highly invasive weed.

It came from Africa and was once widely planted in people’s backyards as a decorative grass. Unfortunately, its resilience and ability to spread quickly has caused big problems today.

You’ll spot fountain grass popping up in Adelaide’s suburban streets and garden beds.
You’ll spot fountain grass popping up in Adelaide’s suburban streets and garden beds.

Fountain grass is now a declared weed, meaning the sale of it is not allowed, it can’t be transported along public roads, and landowners are required to control it.

Drawing highlighting some of the features like fountaining grass, purple to pink seed heads and bristled flowers of the weed
Things to keep an eye out for when identifying fountain grass

What does fountain grass look like?

Fountain grass is an upright grass with leaves that grow close together. It can grow up to 1 metre high.

It has cream, pink or purple flowers with feathery bristles. These flower heads, which grow between 8 and 30 cm long, are made up of lots of small seeds.

These seeds are easily picked up by wind or water, which spreads this weed even further. These seed heads tend to occur in summer, but in milder conditions it can flower for longer periods.

The seeds of fountain grass can remain in the soil for around 6 years, which means any sort of control of this weed has to be followed up, to make sure any remaining seeds haven’t started growing back.

A little seed attached to a feathery bristle, which has come from weedy fountain grass.
A fountain grass seed with attached bristles. Photo: Harry Rose, Flickr

Why is fountain grass a problem?

Fountain grass is escaping gardens, washing down waterways and blowing along roads and getting into national parks, reserves and coastal areas.

You’ll spot fountain grass popping up in Adelaide’s suburban streets and garden beds.
You’ll spot fountain grass popping up in Adelaide’s suburban streets and garden beds.

Fountain grass grows in tight clusters, which crowds out native plant species by stealing their nutrients and water, and smothering them from sunlight.

This has a negative impact on local wildlife because fountain grass clutters previously open spaces, which native animals rely on for basking in, finding food or even spotting predators.

The way that fountain grass forms in tight clusters can also increase the spread and intensity of fires.

Luckily, we can all help stop the spread of fountain grass.

Fountain grass growing out of an Adelaide driveway.
Fountain grass growing out of an Adelaide driveway.

How do you remove and control fountain grass?

Fountain grass can be easy to remove initially, but you will need to check back on areas where it is removed to make sure no seedlings are popping up, because of its long-lived seeds.

When fountain grass is at a seedling or small plant stage, it can be removed by pulling it up by hand when the soil is moist. It can be placed in your household bin. You might like to fill the gap that it leaves in your garden by planting a native instead, such as lemon-scented grass. Check out more native grass options in our planting guide.

Chemical control can be effective to get rid of this weed, but it often requires several treatments. Treatments should occur when fountain grass is actively growing, and ideally before flowering, which tends to be in spring. For advice on chemical options check out the information from our friends at PIRSA on controlling declared weeds in SA.

When fountain grass escapes into national parks, reserves and coastal areas, we work closely with our council partners on controlling this weed to reduce its impact on local plants and animals.

But – as it continues to escape gardens, especially in recent conditions, this task is growing. We can all play a part in lessening the impact of fountain grass by working together and stopping this weed from getting out of gardens in the first place.

Want to know more?

We can all play a part in controlling weeds and lessening their impact. Removing fountain grass from your garden is a great first step in stopping the spread to our more natural areas.

You can learn more about fountain grass or its impact on our native species.

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