How to get rid of crabgrass?

[neilpeace]

I have a heavy infestation of crabgrass on my 1 acre lawn, and removing by hand is not an option. It is now late December. Should I spray now with a post-emergent selective crabgrass spray and then spray again next spring with a pre-emergent spray? The lawn is a mixture of couch, Kikuya and buffalo. I imagine it is better to spot spray, to minimize damage to the lawn. Which herbicide would you recommend for these two situations?

[EricL]

Hello @neilpeace 

Thanks for sharing your question about your lawn.

Dealing with a significant crabgrass infestation in your 1-acre lawn can be challenging, especially with a mix of couch, kikuyu, and buffalo grasses. Given that it's late December, applying a post-emergent selective herbicide now is a practical approach. A suitable option available at Bunnings is David Grays 500ml Crab Grass and Clover Killer Selective Herbicide, which is effective against crabgrass and safe for use on couch lawns. 
 

However, please note that this product is specifically formulated for couch grass and may not be suitable for buffalo or kikuyu lawns. Using it on these grass types could potentially cause damage. Therefore, it's crucial to carefully read the product label and follow the manufacturer's instructions to ensure it's appropriate for your specific lawn composition.

Spot spraying is indeed advisable to minimize potential harm to your desirable grasses. Applying the herbicide directly to the affected areas will help control the crabgrass while preserving the health of your lawn.

Looking ahead to next spring, implementing a pre-emergent herbicide can help prevent crabgrass seeds from germinating. One option to consider is Lawn Solutions Australia 3kg Oxafert Herbicide and Fertiliser, which is registered for use on many warm-season grasses, including buffalo, kikuyu, and couch. 

This product combines a pre-emergent herbicide with a fertiliser, promoting lawn health while preventing weed establishment.

Applying a pre-emergent herbicide in early spring, before soil temperatures reach 55°F (approximately 12.8°C), is generally recommended to effectively prevent crabgrass germination. 

However, it's important to note that pre-emergent herbicides are most effective when applied before weed seeds germinate. Since crabgrass typically germinates in late spring to early summer, applying a pre-emergent herbicide in late December may not provide the desired control.

Maintaining a healthy, dense lawn through proper mowing, watering, and fertilization practices is also essential in preventing weed infestations. A robust lawn can outcompete weeds, reducing the likelihood of future crabgrass problems.

Before proceeding with any herbicide application, it's always a good idea to consult with a local lawn care specialist or the knowledgeable staff at the store to ensure you're choosing the best products for your specific situation.

Please remember to wear personal protection such as gloves, goggles and a mask when using chemical herbicides.

If you need further assistance, please let us know.

Eric

[neilpeace]

Many thanks Eric. I'll do as you suggest and let you know the result.

Neil