How to remove paspalum from your lawn

Paspalum is a common weed that invades lawns, gardens, and other green spaces. This warm-season perennial grass is notoriously difficult to eradicate once it takes hold, making it the bane of many professional and home gardening routines. But, with a few effective strategies and a little persistence, it’s possible to remove paspalum in its entirety and restore both the health and the beauty of your outdoor space.

If you’re currently dealing with paspalum, or want to put mechanisms in place to ensure it doesn’t affect your property in the future, there are a number of methods that can be employed. Keep reading to learn all about paspalum, and discover the best ways to remove it from your lawn – for good – restoring the area to its former glory. 

What is paspalum and how can you identify it?  

Paspalum is a genus of grasses made up of over 300 species. As a perennial plant, paspalum goes through its life cycle in the warmer months. It’s often found in tropical and subtropical reasons and is known for its ability to tolerate salty soils and water, making it a popular choice for use in coastal areas. In Australia, paspalum grows in most coastal regions, including Queensland, New South Wales, Victoria, South Australia, and Western Australia. 

There are two main species that are found in lawns and gardens across Australia – paspalum dilatatum and paspalum notatum. It’s important to understand what these types of paspalum can look like and how they grow, as this will help you to identify them quickly and nip spreading in the bud early on. 

Paspalum dilatatum 

This is the more common of the two species and is also referred to as dallis grass. It’s tall, robust, and grows rapidly, often up to 1.5 metres tall. A tufted grass, paspalum dilatatum is characterised by its light green colour and folded usually hairless leaf blades. This weed is native to South America but is now very widespread in Australia, where it has become naturalised. It has a deep root system and can tolerate a wide range of soil and climatic conditions, including acidic soils, drought, and frost. 

Paspalum notatum

Also known as bahia grass, is a low-growing weed also native to South America that was introduced to Australia as a pasture grass. This type of paspalum has a shallow root system, making it less tolerant to tougher soil and climate conditions. This species of paspalum has a narrower leaf than its counterpart and is lower to the ground with a unique sprawling growth habit. It’s known for its ability to thrive in high-traffic areas and how quickly and densely it can populate a lawn – making it very tricky to remove once it has taken hold. 

How does paspalum spread? 

Paspalum spreads via both rhizomes and seeds. Rhizomes are stems that grow just below the soil’s surface, stealthily spreading the weed without any indication before it’s too late. This is the main reason paspalum is such an unsuspecting weed – it’s very difficult to tell when spreading via rhizomes has begun, and due to the plant’s ability to tolerate almost anything, this can happen at breakneck speed. Both common species of paspalum also spread via their seeds, which can get picked up by the wind, by humans, or by animals. 

How do you remove paspalum from your lawn? 

As paspalum is such a ‘super spreader’, and is notoriously difficult to kill, there are a couple of options for keeping excessive growth under control, including manual removal and various types of herbicide. Let’s break it down… 

Manual removal

The first step to eradicating paspalum is physically removing it with a garden tool like a shovel. It’s important to dig up the rhizomes and roots, and remove as much of this as possible – even a small piece of rhizome left in the soil can quickly regenerate and grow into a new plant! When disposing of the paspalum weeds, place them in the garbage bin rather than composting them to prevent further spread. 

Knockdown or non-selective herbicides 

If manual removal is not possible or is ineffective, another method for removing paspalum from your lawn is to use a knockdown herbicide like glyphosate. This can be applied either via spot spraying or a paint-on application method. It’s critical to note that because glyphosate is a non-selective herbicide, it will kill turf grass and any other plants it comes into contact with. So, when you’re applying it in your garden, be sure to concentrate it on the paspalum alone, and not to get any on your lawn or surrounding plants! 

Selective herbicides 

Finally, there are other types of herbicides known as ‘selective herbicides’ that have proven highly effective at eradicating certain varieties of paspalum. There are two variations of selective herbicides – pre-emergent and post-emergent. They are widely known as the most efficient way to get weed growth under control. But, which one is best for removing paspalum? 

Understanding selective herbicides for eradicating paspalum 

Before you get stuck into removing paspalum and other weeds from your lawn or outdoor area, it’s important to know how pre- and post-emergent selective herbicides work, and what differentiates the two kinds.

Pre-emergent herbicides are applied to the soil before seeds germinate. They work by creating a barrier in the soil that prevents weed seeds from growing and developing into mature plants. While pre-emergent herbicides are not effective at controlling existing weeds, they can be a very beneficial tool to use to reduce the overall volume of paspalum you’re dealing with. Because of the rhizomatic nature of paspalum, it can be incredibly hard to get under control once it is established, so a pre-emergent herbicide provides a good option for first minimising the population of weeds in your garden or lawn. 

Post-emergent herbicides, as the name may suggest, are applied after the weeds have already emerged from the soil and started to grow. They work by infiltrating the weed’s leaves or stems and travelling down to the root, where they kill the plant. Post-emergent herbicides are only effective against already established paspalum plants. 

How to use pre-emergent and post-emergent herbicides

If you’ve decided to go the selective herbicide route to control paspalum in your outdoor area, there are a few things that are critical to note. 

Firstly, both pre-emergent and post-emergent herbicides are available in liquid and granular formats. While there’s debate about which one is better, the rule of thumb is that granular products are often easier to apply for beginners, whereas liquid products provide access to better, more even coverage of your lawn. The product you select will come down to your own personal preferences and the needs of your outdoor space. Pre-emergent herbicides also often come paired with fertiliser, meaning you can weed and feed your lawn simultaneously – and this combination often (but not always) comes in granular form. 

When using either type of selective herbicide, be sure to choose a product that is specifically registered for both paspalum and your type of lawn. Some herbicides are only effective on specific varieties of paspalum and not others, so it also pays to do your research! Like with any herbicide, it is always recommended to follow the label instructions and application rates, as well as general safety precautions. 

If applying a post-emergent herbicide, treatment will be most effective on actively growing weeds – those under stress from drought, disease, or other factors may not be as receptive to herbicide application. If opting for a pre-emergent herbicide, application should be done in conjunction with other weed control measures, such as proper mowing, regular watering, and targeted spot treatments for any fully grown or growing paspalum plants. 

Overall, both pre-emergent and post-emergent herbicides are very potent and successful tools for controlling paspalum in your lawn. However, it’s important to note that like non-selective herbicides, these products can affect other desirable grasses and plants in your outdoor area if not used correctly. 

The best herbicides for removing paspalum 

The one question remaining before you can nip paspalum growth in the bud is this: which herbicide will be the most effective? Here are some recommendations from our team of experts at Specialist Sales.

Non-selective herbicides 

Glyphosate is the most common active ingredient in non-selective herbicides. It should be applied very carefully via painting or spot-spraying application to avoid damaging other plants or the lawn itself, as glyphosate will kill any plant it comes into contact with. Nufarm Glyphosate 450 Herbicide or Rapid Fire 800 SG Glyphosate Herbicide are two suitable options for successfully eradicating paspalum. 

Pre-emergent herbicides 

If you’re looking to use a pre-emergent selective herbicide to control paspalum at the seed stage, there are a number of excellent products available on the market. Pre-emergent products that will provide residual control against paspalum, preventing regeneration in your lawn, include Spartan, Barricade, ProForce Duke, Destiny, and Onset 10GR herbicides. Both Spartan and Onset herbicides are effective at treating both paspalum dilatatum (Dallas grass)and paspalum notatum (Bahia grass), whereas Barricade, ProForce Duke, and Destiny are suitable for use on bahia grass only. 

Post-emergent herbicides 

Monosodium methyl arsenate (MSMA) and disodium methyl arsonate (DSMA) are types of post-emergent herbicides that have been found to successfully eradicate paspalum without harming other grasses in your lawn (depending on your lawn type). Effective options include Militate MSMA, Monopoly MSMA, and DSMA Selective Herbicide. As with all herbicides, be sure to understand the benefits and constraints of the product to ensure no damage is caused to your outdoor area or surrounding plants. 

Other techniques for controlling paspalum

In addition to physical removal and the application of herbicides, there are a handful of other practices that will help prevent paspalum from invading your lawn or garden in the first place! Employ these methods to minimise the potential risk of harm to your outdoor space. 

• Proper mowing: Be sure to mow your lawn correctly and maintain the correct height for your grass type to prevent paspalum from taking hold. 
• Fertilisation: Fertilising your lawn regularly with a balanced fertiliser will keep your grass healthy, strong, and less susceptible to weeds. 

• Irrigation: Water your lawn deeply and infrequently rather than giving it frequent, shallow bursts of water. This will encourage your grass to develop a deeply entrenched root system that’s more resistant to invasion. 
• Aeration: Finally, aerating your lawn once to twice a year can improve soil health and reduce the risk of weeds like paspalum forming. 

While removing paspalum from your lawn can be a challenging process, with the correct tools and some effective maintenance, it’s completely possible to turn things around and reinvigorate both the health and appearance of your lawn or garden.

Specialist Sales have been assisting turf enthusiasts and home gardeners alike with the management of paspalum and other weeds in their lawns for over a decade. If you’d like help selecting the right product or need advice on your next steps, get in touch with our friendly team on 1800 780 317.