Last Updated on June 29, 2021 by Grow with Bovees
Grass turning yellow can be a depressing sight. There’s nothing quite like a lawn losing its luscious color to send a proud gardener into a pique.
But what causes this loss in color and vitality? And is there anything that can be done about it? Well, yes, as a matter of fact, there is.
But before we get to that, we need to understand some of the reasons for grass blades turning yellow.
Grass Turning Yellow
Among the most common causes for a yellow lawn are disease, a lack of nutrients, or the simple fact that your lawn has gone to sleep in order to protect itself—a phenomenon known as lawn dormancy.
Let’s take a look at these and other possible causes for yellowing grass in a little more detail.
Lawns have a tendency to suck in a lot of nutrients. A lack of nutrients is the most common reason for a yellow lawn. Nutrients such as nitrogen, potassium, and phosphorus are essential to lawn health. However, in grass, it’s usually an iron deficiency or nitrogen deficiency that leads to grass blades losing their color and developing yellow spots.
A lack of iron will also result in stunted grass blade growth, which doesn’t help matters because it results in inconsistent, patchy turf.
Conducting a soil test will help establish where deficiencies in your grass lie, allowing you to treat your lawn with the appropriate fertilizer.
If a soil test indicates a nutrient deficiency, it’s high time to get out the fertilizer. Using fertilizer is the most effective way of ensuring your grass gets the nutrients that it lacks.
Top Dressing and Overseeding
As well as fertilizers, top dressing and overseeding can improve grass conditions by replacing missing nutrients and creating the ideal conditions for new seeds to germinate. In this way, the problem areas in your lawn, which have lost their color and luster, can be repaired without interfering with healthier areas of your lawn.
Properly applied, top dressing shouldn’t be too thick as it might suffocate your grass. The idea is that existing grass should be allowed to grow through, while less healthy grass is revived.
Top dressing is also a very effective way of dethatching.
Even though we have been extolling the virtues of nitrogen in relation to grass growth and vitality, you might be surprised to hear that too much nitrogen in a fertilizer can have an adverse effect on the health of your grass and cause it to lose color.
An excess of nitrogen in fertilizers can not only cause unsightly discolored streaks and spots on your lawn, but also chemical burns to grass roots as well as altering pH levels of soil. Just to be clear, pH is the measure of soil acidity or alkalinity. Having the correct pH is vital for healthy grass.
Often the result of over-enthusiastic fertilizing, this imbalance illustrates the importance of the soil pH tester in establishing the correct nutritional requirements for your grass. Because overdoing it can have serious consequences.
Other Causes of Nitrogen Excess
Believe it or not, dog urine is another major culprit in contributing to too much nitrogen. Dog urine contains a high concentration of nitrogen and can cause significant discoloration to an otherwise pristine lawn—usually in the form of yellow spots.
To avoid this eventuality, coax or train your dog to relieve itself somewhere other than the lawn, or if it has to, then at least not pee on the same spot twice. If you do catch them going on the lawn, immediately pour on water to flush the area and limit any damage.
Disease is another common reason for a yellow lawn. Most lawn diseases are fungal in source. These can include snow mold, fairy rings, dollar spot, fusarium, and smut, among others. In these cases, it is essential to control the moisture levels and ensure the lawn is well aerated.
By watering in the morning and removing any thatch or clippings from the surface of your lawn, you will ensure that excess water either drains away or evaporates.
Good irrigation and drainage play a key role in preventing the conditions that fungi thrive in. Also, keeping the grass short by using a lawn mower frequently, combined with the use of core aerators and rakes, will create the “airy” environment that lawn diseases really hate.
In the United States, chinch bugs are an all too common reason for yellow spots appearing on lawns. Particular attention should be paid to these pests.
There are a number of simple DIY tests to establish whether chinch bugs are the cause of your yellow grass. If the results prove positive, then it’s time to remove any thatch as well as to make sure there isn’t an excess of nitrogen in the soil—chinch bugs thrive on nitrogen. Lawn aeration and top dressing are also effective.
And if that doesn’t do the trick, you could try insecticides, but this should really be a last resort. Insecticides are a danger to children and pets, not to mention the environment. Moreover, insecticide treatments of chinches are often counterproductive because they can kill insects that control chinch bug numbers.
In other words, it would be wise not to tamper with the healthy ecosystem of your garden, and by doing so, interfere in biological control.
Lack of Water
We have so far only talked about too much water; now it’s time to address the question of too little. Excess dryness brought on by extreme heat can be just as damaging to a lush layer of turf, causing it to turn yellow. Dehydrated grass will quickly form yellow spots and lose its luster. If left too long in this state, serious damage to your lawn might occur.
In such conditions, it’s necessary to water the lawn with greater frequency. Still, even here, it should be remembered that watering in the day is advisable if you wish to avoid the damp and dark coming into contact to provide the perfect breeding ground for potentially harmful fungal lawn diseases.
Another possible reason that causes lawns to turn yellow is something called “lawn dormancy”. Lawn dormancy is when your grass goes to sleep in order to protect itself from harsh weather conditions, such as during the cold or dry seasons.
After all, if there’s precious little water around, it makes sense to conserve what little you have in order to keep your roots alive. The same is true when there’s frost about.
During this period, it is critical that you continue with your regular lawn care program by watering, mowing, and removing weeds if you have to. The idea is to reduce the dormancy times and accelerate recovery as much as possible.
Rest assured, your lawn will bounce back.
This leads us to the use of your lawn and the impact that can have on the vitality and color of your grass.
Soil compaction from too much walking on the lawn can cause the pores in soil to close. This, in turn, has a negative impact on grass roots, as well as preventing water and nutrients from finding their intended target.
Core aerators and rakes are your allies in loosening up the soil enough so that the grass roots can breathe and feed again.
If you believe prevention is better than cure, make a conscious effort not to walk on the compacted area wherever possible.
A footpath or stepping stones strategically placed might be a solution if the grass cannot be avoided.
What Causes Yellow Grass?
Numerous factors cause lawns to turn yellow, from a lack of nutrients, to disease, to over fertilization. To further complicate things, grass can simply fall asleep in order to protect itself from harsh weather conditions. The key to best practices is to quickly establish the cause and then to take the relevant actions.
How Can You Fix It?
It is important to remember that color and vitality can be restored to yellow grass. A soil test will give you a pretty good idea of where a nutrient deficiency might exist. Good lawn maintenance practices of mowing, aerating, and watering correctly should see off any lawn diseases that might be around.
If the yellow lawn has been brought about through over usage then it might be a good idea to think about incorporating possible design solutions into your lawn. For example, a footpath or stepping stones.
Will Over Fertilized Grass Grow Back?
Over fertilized grass suffering from what is known as “fertilizer burn” can grow back. As long as it’s not already dead. And you need to be sure, because the grass might simply be dormant in an attempt to protect itself rather than dead.
Assuming there is hope and that it is still alive, then flushing out the affected areas with generous quantities of water will help revive it. Watering in this way for about a week should be sufficient to return the fertilizer burned areas to their old self.
How Do You Fix Dead Yellow Grass?
Assuming that you have established that your yellow grass is really dead (a simple “tug” test will do) rather than just lying dormant, then revival is out of the question. Instead, it’s time to rake up the dead grass and spread new seeds. Obviously, fertilizer will speed up the process by providing all the necessary nutrients.
So that about wraps up proceedings. Yellow grass, once it arrives, does not have to be a permanent fixture of your lawn. By isolating the problem and acting, discoloration can be quickly halted and reversed. Good lawn maintenance and practices are the key to a healthy and vibrant-looking lawn green that doesn’t turn yellow.
And it is these good practices, in combination with the knowledge of underlying causes, that will help quickly restore your precious lawn to its past glory.