Zoysia Grass Turning Yellow in the Fall/ Winter
Last updated: 8 March 2024
Zoysia grass is renowned for turning yellow in the fall and winter when grown in colder climates.
It hibernates in winter, as cold weather just isn’t its thing. You can do a few things to mitigate this and help it turn green again in the spring.
Dormant Zoysia Grass
QUESTION: My grass turned yellow in the fall. I am unsure of the type of grass, but this is the second year the grass has turned yellow. It has been an established lawn for over 25 years. I had a soil test performed; the Phosphorus and Magnesium levels are optimum, and the Potassium is below optimum (53ppm). Should I kill the existing grass and reseed it, or is there a better solution?
ANSWER: It sounds like you have a Zoysia grass lawn. Zoysia grass has been touted as “the miracle lawn” for the Midwest. Zoysia is a warm-season grass. Warm-season grasses thrive in the summer heat and go dormant, turning brown/yellow in the fall. See this link for more information on Zoysia: Zoysia Grass
You have a couple of options:
- Kill the existing grass with a non-selective herbicide such as 41% glyphosate (which is Roundup – but look for the generic brands, as they are much cheaper). Then seed it with a slit-seeder.
- Strip the existing grass with a sod cutter, then re-sod with Kentucky bluegrass.
- Over-seed the zoysia with a perennial ryegrass/Kentucky bluegrass seed blend in the fall. Over-seeding will not get rid of the zoysia however it will keep it green over the winter.
The main reasons for grass turning yellow are over-watering or an incorrect pH level. Most grasses like a natural pH of 7, but some exceptions exist. Speak with your local specialist who can treat your soil to return your lawn to its former glory.
Note: If you have Zoysia grass, it has turned yellow or brown because it is too cold, and the lawn has gone dormant. You will need to wait it out.
Does fertilizer bring back yellow grass?
If the issue is your soil, then fertilizers can help adjust the imbalance in pH by adding nitrogen. This can also be achieved by using soil compost. See below for recommendations.
Best Fertilizers for Lawn Grass
How long does it take yellow grass to recover?
If the cause is identified and the correct remedies set into place, in ideal conditions your grass can turn green again in as little as 7 days, but in most cases it will take 12 – 20 days.
Why does grass turning yellow in winter?
In most cases, it will be because you have a grass species poorly suited for colder temperatures. Grasses like Zoysia go into hibernation and turn yellow and brown until spring comes around and the weather warms up again.
You can remedy this by switching to a grass species like Kentucky bluegrass, Perennial ryegrass or Fescue grass.
Should I be watering yellow grass?
In most cases, yellow grass does not mean a lack of water. It can be put down to either;
- Overwatering.
- Poor pH levels in the soil.
- Warm-weather grass hibernates during the cooler months.
Giving the grass more water in all three cases will not fix the problem. If the pH is not ideal, you will need to fertilize it; if it’s going into hibernation, you must wait until spring for it to return or replace it with a grass species better suited to cooler climates.