How to Get Rid of Peppercress in Australian Lawns

While it’s classified as a weed on Australian shores, this tap-rooted plant is eaten in other parts of the world. For the purposes of this article, we’ll focus on how to identify it and how to manage it.

Peppercress can be found across most of southern Australia. Originally from Africa, it has adapted well to the Australian climate. It has become so naturalised and is so common in Australian bushland that it can appear native.

As the plant grows, the florette of leaves that will be largely ground-based in its infancy will grow up on a wiry stem. The leaves of the plant are long and thin, and depending on the variant, might be covered in a fine fur or have slightly serrated edges.

Peppercress does produce tiny flowers along a stem that can be up to 15cm in length, and spreads via seeds held in egg-shaped seed pods.

It can be found in a variety of turf types but is especially problematic in warm-season grasses like Buffalo, Couch, Bermuda, Kikuyu, and Zoysia due to its slower winter growth, which gives this cool-season weed an opportunity to establish.

Peppercress is most active during the cooler months of the year, typically germinating in Autumn and Winter before flowering and seeding in Spring.

Peppercress thrives in disturbed soils and often takes hold in weak or patchy areas of lawns where the turf has thinned out due to stress or poor maintenance. It spreads rapidly via seed, with each plant capable of producing thousands of tiny seeds that can remain viable in soil for several years, reinforcing the importance of maintaining a pre-emergent weed barrier to stop foreign weed seeds germinating in the soil so they never become a problem in the canopy of the lawn.

Manual Removal

For homeowners looking for natural or manual methods, hand-pulling can be effective, especially when the weed is young and the soil is moist. It’s important to remove the entire root system to prevent regrowth.

Using Herbicides

For a more proactive approach, selective herbicides can be used. While few commonly available herbicides are specifically registered to control Peppercress, those containing moderate to high concentrations of Dicamba like Contra M Duo have shown efficacy against Peppercress, though this selective herbicide is not safe for us on Buffalo lawns.

To ensure efficacy on the first application of any herbicide, it’s recommended to apply in conjunction with a surfactant like Wetter 600 for improved adhesion to the leaf.

Alternatively, for stubborn weeds or for isolated outbreaks, using a non-selective herbicide is always an option. PCT Glyphosate 360 will affect any plant it comes into contact with so blanket spraying is not recommended. Some lawn lovers opt to dab non-selective herbicides like Glyphosate-based products onto the leaves and crown of the plant using a small sponge or brush.

When using chemical treatments, always follow manufacturer instructions when it comes to necessary protective equipment and safe re-entry times for humans and animals. Apply on a dry day with minimal wind to prevent drift onto desirable grasses.

Natural Remedies

Peppercress can be removed from your lawn without the use of chemicals by hand-pulling the weed. Natural herbicides and solutions like vinegar or boiling water will cause the leaves to wilt and die, but will be almost entirely ineffective against Peppercress’s root system.

To prevent Peppercress from returning, applying a high-quality pre-emergent herbicide is a proactive solution. Pre-emergents work by creating a barrier in the soil that inhibits seed germination, effectively stopping weeds before they establish.

A good pre-emergent herbicide, such as those containing Prodiamine (like Spartan in liquid form, or Onset GR in granular form) or Oxadiazon (like Echelon Duo or Oxafert), offers up to six months of protection against a broad range of invasive weeds.

This long-term approach not only reduces the need for repeated manual or chemical interventions but also contributes to a healthier, more resilient lawn with less pressure from invasive weeds.

Whether you’re looking for a quality pre-emergent to minimise the risk of Peppercress invading your much-loved lawn, or you need a post-emergent herbicide to control a Peppercress outbreak, you’ll find all the supplements and chemicals you need to keep your grass in top shape at the myhomeTURF Online Shop; home to hundreds of market-leading products that ship Australia-wide.