Anyone who takes pride in their garden knows the frustration of a yellowing lawn. Kikuyu grass is a beautiful and popular variety that has a particular reputation for losing its lush, green colour when exposed to the wrong elements. This can leave even the most experienced lawn-carers tearing their hair out and re-evaluating their whole system of maintenance.
So, why does Kikuyu grass go yellow? There are a few simple reasons why Kikuyu or any type of grass can go yellow. Thankfully, they’re usually relatively easy to address so you can get your lawn looking green in no time.
If you’re noticing rings or circles of brown or yellow grass, the cause may be a fungal disease such as Kikuyu Yellows. These diseases usually appear around spring and summer, especially when the soil is warm and damp.
Diseases such as this work by infecting the root system, causing root rot and dying grass. There is currently no cure for Kikuyu Yellows but applying fertiliser can help mask the condition. Certain fungicides may help for other fungal diseases.
Ultimately, prevention is the best way to keep diseases away from your lawn. Improving drainage and only mowing when the grass is dry are great ways to prevent fungal diseases from taking hold.
Nutrient deficiency is a common culprit for lawns yellowing, regardless of the type of turf you have. If the soil is lacking essential nutrients such as nitrogen and iron, your lawn can become patchy and discoloured.
A simple way to find out if your soil is lacking nutrients is by applying fertiliser. If you start to see noticeable improvements, the soil was most likely nutrient deficient. For more accurate results, you can purchase a soil testing kit to check the pH.
On the flip side to nutrient deficiency is over-fertilisation. Chemical fertilisers contain mineral salts, which can build up and dry out your lawn, causing ‘fertiliser burn’.
If your lawn reacts negatively after fertilising, grab the hose or turn on the sprinklers. This will start to dilute and flush out the chemicals. Keep up watering each day for a week or so, preferably in the morning so your lawn has time to dry out in between.
Both watering your lawn too little and too much can cause discolouration. Watering your lawn too little causes it to dry out, particularly in the warmer or dryer months. Watering too much flushes out the nutrients that are essential for your lawn to remain healthy.
Discovering the right watering pattern for your lawn will make all the difference here. Usually, watering deeply 1-2 times a week helps your lawn get the moisture it needs without diluting the nutrients.
Both hot and cold weather conditions can cause your lawn to lose its colour. Hot temperatures cause the lawn to dry out and burn, while cold temperatures can bring frosts that leave the lawn lifeless.
Correct watering and fertilising can help keep your lawn healthy even in the most extreme weather conditions.
Another common cause for lawn discolouration is pests, particularly small insects and grubs. These pests get into the root system of the grass and wear them down, meaning the grass doesn’t get the nutrients it needs to survive.
Insects can be prevented by fertilising and irrigating properly. There are also a number of pesticides available that can help address the problem.
If you’re noticing small patches of yellow or brown on the grass, it may be a result of your canine friend. Dog urine is high in nitrogen, which can be deadly to your grass in high concentrations.
The best way to combat this is to train your dog to go in a particular place in the garden. If this isn’t possible, watering the area that your dog has just urinated on can help dilute the nitrogen-rich substance.
Caring for your lawn takes time and energy, but the investment is well worth it. If you need any assistance in caring for your lawn or choosing the perfect turf, get in touch with Rivers Edge Turf on 02 4579 9009.