How to remove invasive grasses from your lawn
Kikuyu and couch are the number one suspects when it comes to lawn invasion, they are fast growing and have fine seeds that can spread very easily. Kikuyu is more aggressive in nature than any other lawn variety, so it’s potential to take over is very high. Kikuyu spreads by both runners and by seed.
Invasion can occur a number of different ways:
- Your original lawn and soil not being sprayed out and killed off properly and re-emerging from seeds or runners.
- Grass seeds that have travelled to your lawn by the wind, on pets, in bird droppings, on clothing or shoes, or from a neighbouring lawn.
Some lawns, like DNA Certified Sir Walter, have a growth habit that will usually crowd out most weeds and unwanted grasses. Occasionally these undesirables will invade, especially if your lawn hasn’t been well maintained. But it’s important not to confuse your weeds with your grasses. Weeds are generally soft round plants whereas unwanted grasses can include things like paspalum, kikuyu and couch, depending on what lawn variety you have.
Unfortunately in most cases, many warm season grasses are unable to be selectively treated in other grasses. So there are no specific herbicides that can be recommended to blanket treat a lawn without harming the grass you intend to keep as well. But there are other ways to handle the infestation.
Pull it out by hand
If the invading area is only small the most effective way to remove an unwanted grass variety is to pull it out carefully by hand. You can also chip them out with a mattock or a garden spade. This method can be time consuming if the invading grass has spread considerably. But through regular hand weeding, ensuring you remove as much as possible and all of the roots, you should begin to get on top of the infestation. A healthy lawn should also help to thicken and choke out more emergence, so regular lawn care activities will also be important for success.
Spray with a non-selective herbicide
The only other way to remove kikuyu or couch from a buffalo, fescue, rye or bluegrass lawn is through the application of a non-selective herbicide like glyphosate (Round Up).
By using a small paint brush or weed wand carefully brush the leaves of the invading grass. Please be aware that glyphosate is a non-selective herbicide and be careful to only touch the invading turf variety and not your lawn, as it will die also if it comes into contact with the herbicide. Invading grasses like kikuyu, tend to grower quicker and taller, so the best time isolate the grass is to do so when there is a little bit of length to the lawn. This may also allow for careful ‘wick wiping’ of the invading grass if there is extensive contamination across the whole lawn area.
How to remove kikuyu in couch
For a couch lawn that is suffering from an invasion of kikuyu, there are some selective herbicide options that will treat kikuyu but not the couch. There is a commercially available herbicide called Monument, which can be used to suppress Kikuyu from couch lawns. Monument Herbicide is the broadest spectrum selective post-emergence herbicide for turf. Monument is highly effective in controlling Poa annua, Ryegrass, Kikuyu, Sedges and a wide spectrum of broadleaf weeds.
Monument Liquid Herbicide is safe to use on – Common Couch, Hybrid Couch, QLD Blue Couch and Zoysia – DO NOT USE on Kikuyu or Buffalo.
