When your new sod is turning yellow, it usually means it is getting overwatered.
Yes, new sod is supposed to be watered more than the grass in an established lawn, but the longer it has been since the sod was planted, the lower the frequency of watering should be. Make sure you do not soak more than just the first few inches of soil with water.
Other common causes of yellowing sod are pet urine, soil quality, too much fertilizer, fungi and insects, poor installation, and mowing the sod too soon.
This article discusses the reasons your new sod is turning yellow, and what you can do to fix it.
Why is my new sod turning yellow?
The sod is overwatered
If you see yellow patches on your new sod, you are probably giving it too much water. Fresh sod does need more water than a regular lawn because you want the roots to grow, but you have to reduce the watering over time.
New sod is watered three times a day for five to ten minutes for the first ten days after installation. Each watering should only soak the first couple of inches of soil. After the tenth day, decrease the watering to once a day and only soak the top quarter-inch of soil. After three weeks from installation, you only need to water the sod every other day for a week, and after it has been in place for a month, you can just water your lawn once or twice a week.
Your pet’s urine
Your dog’s pee can burn your new sod and even older lawns, because of the high nitrogen content of the urine. This can also cause the sod to have yellow or brown patches. If you can do so immediately, hose down the area where your dog just urinated to wash away the urine. You can also train your dog to pee in a more discreet area of your lawn and discourage it from going in the middle of the lawn.
Use
Too much walking or activity on the new sod can also cause it to turn yellow. Try not to walk on the newly-installed sod for four weeks after installation. You need to give it time to properly establish its roots, and it can only do this if it is not disturbed. If you absolutely have to tread on the sod, try not to walk the same path every time. Discourage others from walking on the sod by marking the perimeter with some tape or string.
Soil quality
When you install new sod near trees or bushes, it is possible that these areas will soon start to become yellow. This is because the trees and bushes will take the nutrients from the soil, leaving very little for the sod. The lack of nutrients will make it even harder for the sod to establish roots. The trees and shrubs will also keep sunlight away from the sod, which it needs when trying to establish itself. A great approach in this situation is just to put mulch or decorative rocks in these areas, instead of using sod.
Too much fertilizer
You do not need to fertilize newly-installed sod until after at least 30 days after installation. Fertilizing sod too early can result in yellow patches because the immature root system cannot absorb nutrients effectively, so the nitrogen from the fertilizer will just leach into the soil.
Most sod is fertilized before harvesting anyway, so you do not have to be in a hurry to add more. If you see the yellow patches after applying fertilizer, just water these areas so the nitrogen can be diluted.
Fungi and insects
There are some species of fungus and insect that can cause your sod to turn yellow. It may be difficult to assess what organism is attacking your lawn, so you will have to do your research regarding fungi and insects in your part of the country. If you are able to contact your local agriculture agency, they could help you with the information you need regarding the organism and how to get rid of it.
You are mowing the lawn too soon
If you mow the sod a little too soon after installation, this may also cause it to turn yellow. The only way to prevent this is to avoid mowing your lawn until after the patches have healed. It is also best to allow the grass to grow a little longer than usual. If the weather has been warmer than normal, try not to cut the lawn too short.
Poor installation of the sod
If the sod was not installed properly, this can also be a reason for it turning yellow. If there are air pockets trapped under the sod, this keeps the sod from properly forming roots in the soil since it might not be able to reach it. The roots stuck in the air pocket will dry out and die.
If you suspect a poor sod installation job, take plenty of pictures as evidence and contact the sod company that installed it to tell them about your concerns. If they come by to inspect the sod and realize they may have done a bad job, they should be willing to fix it for you.
Conclusion
If your new sod is turning yellow it is most probably getting overwatered. Remember that, even though new sod does need to be watered a lot, the frequency should be gradually reduced the longer it has been since installation.
Other causes of yellowing sod include pet urine, soil quality, too much fertilizer, fungi and insects, poor installation, and mowing the sod too soon.
If you are able to leave the sod as undisturbed as possible for the first month after installation, it should minimize the occurrence of any yellowing issues.
Image: istockphoto.com / sandsun