If your lawn has yellow patches after mowing, this could be caused by a lack of water. Your lawn may also turn yellow after you mow because your mower blade is dull and is damaging your grass. A yellow lawn could also be caused by fungal lawn diseases that damage your grass. Additionally, a lack of soil nutrients will cause yellow grass. To combat yellow lawns, water deeply, sharpen your mower blades, treat your lawn for fungal diseases, and fertilize your lawn regularly during the growing season.
Table of Contents
4 Reasons Why Your Grass Turns Yellow After You Cut It
Lawn yellowing is a frustrating lawn care experience. While it may seem to happen at random, there are a few key causes that may be triggering this reaction. Here are some common reasons your grass may turn yellow after it’s cut:
Lack of Sufficient Water
Insufficient water is the most common reason for lawns to turn yellow. While green grass is a highly resilient plant, it suffers without adequate water and struggles to maintain its color. This is why a lawn is most likely to yellow in summer. During high heat periods, it’s difficult for your grass to retain water. As a result, lawns dehydrate quickly.
- Dehydrated grass yellows quickly, especially when the additional stress of mowing is factored in.
- Institute a regular watering schedule during dry weather months to combat rapid water loss if you are able to.
It’s best to institute a watering routine during dry weather conditions to combat dehydration. This may not always be possible depending on drought restrictions. However, if you are able to, it’s best to water your lawn 1–3 times per week in the summer. Be sure to water early in the morning to prevent water from evaporating.
Excessive Lawn Damage
Lawn mowers can be fairly traumatic to your lawn. Dull mower blades will tear, shred, and even uproot grass rather than cut it neatly. This can result in damage to grass roots that may cause your lawn to yellow and even die. You’ll need to sharpen your mower blades 1 to 2 times per year to avoid these issues.
- Dull lawn mower blades can damage your grass instead of helping keep it neat.
- Sharpen your lawn mower blades to protect your grass.
Always be sure your mower is unpowered and safely disassembled before attempting to sharpen the blades. Wear protective goggles and heavy gloves while sharpening. Clamp the lawn mower blade in place securely and begin sharpening with an angle grinder or similar tool. Always angle the blade away from yourself to avoid accidents. If you don’t feel comfortable sharpening your own mower blades, you can have your lawn mower serviced by a professional.
Lawn Fungus or Lawn Diseases
A fungal infection or other lawn diseases can give your lawn yellow spots quickly. Fungal disease needs to be identified quickly and combated with a lawn fungicide. Other lawn diseases like lawn rust may require different treatment.
- Fungal lawn disease can quickly turn a green lawn yellow.
- Look for signs of fungal disease, lawn rust, and other harmful diseases.
- Treat your law as quickly as possible with this lawn fungicide before the disease spreads.
If you are unsure if your lawn is infected with fungus, call in professional help in identifying lawn grass diseases. Experts at your local garden center can pinpoint the disease and help suggest potential remedies.
Soil Issues or Lack of Nutrients
Nutrient deficient lawns will yellow as a result of not getting sufficient nutrition. This can be caused by issues in the soil itself or insufficient fertilizing. Consider using a hybrid fertilizer schedule that combines organic fertilizer with a high-nitrogen fertilizer. This combination of iron-rich organic fertilizer with fast-acting nitrogen fertilizer will result in a green lawn.
- Lack of nutrients can cause your grass to yellow.
- Nitrogen and iron-rich fertilizer contribute to a green lawn.
- Excess fertilizer can cause grass yellowing or browning, so use fertilizer according to the instructions on the bag.
- Fertilize your lawn 5–6 times per year to safely offset poor soil conditions.
It’s important to note that excess use of high-nitrogen fertilizer can dry out your lawn, which causes more yellow or brown grass. This is known as “fertilizer burn.” To avoid this, make sure to use organic, slow-release fertilizer and provide your lawn with plenty of water. Adding nutrients to the soil will drastically improve the color of your grass.
Can Yellow Grass Turn Green Again?
Even if conditions have turned your grass yellow, your lawn can be saved as long as the grass is not completely dead and brown. Dead grass is beyond saving. Yellow lawn grasses can often be revived with increased watering, fungicidal treatment, and/or fertilization.
- Yellow grass can be saved but brown grass cannot.
- Most yellowing can be solved with increased watering, fertilizer, or a fungicide treatment.
- Lawn diseases will need to be diagnosed and carefully treated.
If the issue is caused by lawn diseases, you will need to seek professional help to treat your lawn. Consult with your local garden center to identify the disease or fungus. Once you know the disease, you can begin working on the treatment or cure.
How Do You Fix Yellow Grass After Mowing?
The most effective way to salvage your green lawn once it begins yellowing is to increase watering. Be sure to add regular watering to part of your lawn care routine in dry weather as long as you’re not under drought restrictions. A healthy lawn can bounce back from yellowing very quickly if you’re meeting all its basic needs.
- Most yellowing issues can be solved through proper watering.
- It’s a good idea to use this slow-release, organic fertilizer to boost the color of a yellow lawn.
- Be careful to make sure you are providing the correct amount of fertilizer per application.
It’s best to start with a slow-release fertilizer when repairing a yellow lawn. This will add essential soil nutrients without risking fertilizer burn that can dry out grass. You can also mix it with other fertilizers for a hybrid approach.
Why Is Your Grass Not Green After Mowing?
Yellowing lawns can be caused by many issues. Here are the most common issues and how to resolve their effects on your lawn grass:
- Lack of sufficient water can dehydrate your lawn.
- Dull mower blades can cause excessive damage to lawns, turning the grass yellow
- Fungal lawn diseases can turn green grass yellow.
- Soil issues and lack of fertilizer can turn your grass yellow.
- Water your lawn deeply 2–3 times per week to increase the natural green color.
- Sharpen your mower blade 1–2 times annually to prevent grass damage.
- Apply a fungicidal lawn treatment if your lawn is diseased.
- Use slow-release fertilizer to green up your lawn and supply soil nutrients.
With these methods at your disposal, you know all you need to counteract lawn yellowing. Lawns may be resilient but they still have the same needs as any other plant. Treat your lawn well and it will reward you with rich, green coloration.
