How to Get Rid of Bahia Grass (Paspalum) in Your Lawn

‘Bahia Grass’ scientific name is Paspalum notatum, which is why it’s more commonly known as ‘Paspalum’. It is an aggressive, warm-season perennial grass that thrives in hot, humid climates. It is commonly found in northern and coastal regions of Australia, including Queensland, New South Wales, and parts of Western Australia. Paspalum is particularly invasive in home lawns, sports fields and pastures due to its deep root system and resilience in poor soil conditions.

Physically, Paspalum has coarse, V-shaped seed heads with distinctive purple or black seeds, which stand out against its tough, wiry blades. It spreads through both seeds and underground rhizomes, making it difficult to eradicate once established.

The weed is most active during the warmer months, from late Spring through to early Autumn, and is particularly problematic in Buffalo, Couch, Bermuda, Kikuyu and Zoysia lawns, where it competes aggressively for nutrients and space.

Paspalum’s tall, seed-laden stalks help the plant spread voraciously, and seeds will germinate just about anywhere, including thinner areas of your home lawn or right in the middle of the healthy canopy.

The plant establishes a robust root system which in turn makes it outcompete the lawn for nutrients, while its spear-shaped leaves will protrude above most home lawns and win the battle for sunlight and nutrients.

The seeds are easily disrupted and can be spread by wind or in downpours of rain, and can be carried on pet fur, clothing or by birds.

Manual Removal 

Manually removing Paspalum outbreaks is an effective and chemical-free control option, however disrupting the plant does increase your chance of spreading seeds. Thanks to its fibrous root system that deeply entrenches itself in the soil layer, manual removal can be a very physical task that can yield poor results in terms of regrowth.

Using Herbicides

Very few products available to the home lawn lover market themselves as effective against Paspalum. David Gray’s Crab Grass and Clover Killer states on the label that it selectively controls (but is not registered for) Paspalum and several other hard to kill invasive weeds, and testing has shown it to be effective, however its active ingredients mean that it’s only suitable to blanket spray on Couch and Bentgrass lawns. Kikuyu and Buffalo lawns will need to be spot-sprayed to minimise the trauma to the healthy plant, and established plants can take several applications of this product to completely knock it down.

Outside of this, chemical control of Paspalum will require the use of harsh, non-selective herbicides like Glyphosate, often with a surfactant like Wetter 600 to help it stick to Paspalum’s woody stalks and waxy leaves. Unlike selective herbicides which are fine to blanket spray and won’t harm your desirable lawn, non-selective herbicides need to be used very sparingly and in a very directed manner as they’ll kill any plant they come into contact with.

Non-selectives can be used in a spot-spray method which may include some collateral damage. Alternatively, some lawn owners choose to delicately paint the herbicide on to the leaf and crown of the weed to minimise collateral damage, however this method does increase your risk of contact with the herbicide.

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

There are no natural remedies for the effective control or eradication of Paspalum from home lawns.

To prevent Paspalum 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 (such as 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 Paspalum invading your much-loved lawn, or you need a post-emergent herbicide to control a Paspalum 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.