With how much effort you put into mowing, fertilizing, and otherwise maintaining your lawn, the last thing you want to wake up to is a lawn that is yellow, dry, and burnt.
Burnt grass isn’t just unsightly. If your lawn is turning yellow or brown, it’s also a clear sign that something more is going on beneath the surface. More often than not, burnt grass is a direct symptom of stress or damage to the root system.
Several things can cause burnt grass. Some are more serious than others. The good news is that — when diagnosed and treated promptly — nearly all cases of burnt grass can be returned to their former green glory.
In this article, I’ll cover some of the most common reasons formerly lush turf can develop a burnt appearance. I’ll also explain how to get dead, burnt grass to grow green once again.
What Causes Grass to Burn or Die?
Burnt grass may present as yellow or brown grass with a dry texture. This foliar damage is indicative of something stressing the root system. Depending on the exact cause, you may notice burn damage develop in isolated patches or across your entire lawn.
Burnt grass may or may not be dead. However, already damaged blades will not heal even with treatment. If the root system remains intact, though, you will see new, green grass take the burnt blades’ place.
Again, burnt grass is not necessarily dead. But leaving this symptom undiagnosed and untreated for even a short amount of time greatly increases the chance of permanent damage to your lawn.
Fertilizer is often touted as a miracle product that can treat any and all problems in the lawn. However, too much fertilizer can do more damage to turf grass than never applying it in the first place.
Fertilizer burn occurs when too much fertilizer is applied at one time or when not enough water is available with the fertilizer.
Over-fertilizing is most often a problem when using nitrogen-rich formulas. Since nitrogen is the most important nutrient for plant life, including grass, this fact can make proper nutrition a bit tricky for the average person. Measuring all fertilizer applications is crucial to maintaining your lawn and preventing root damage caused by overfeeding.
Most nutrients in fertilizer are delivered in the form of salts — we’re talking about “salt” in the chemical sense rather than what you use to season your food. Like table salt, however, these nutrient salts absorb significant moisture from the soil. The result is much less water being available to your lawn’s root system and an increased chance of fertilizer burn.
All dog owners are familiar with the toll their pet’s day-to-day bathroom habits can have on a lawn. Of course, it’s not just dogs that can damage turf grass in this way. But in most neighborhoods, they’re the most likely culprits.
Animal urine is high in nitrate salts. This is why animal urine and fertilizer burn often look identical to each other.
Since animal urine contains nitrogen, it can sometimes turn grass green and encourage faster growth. If animal urine is the cause of your burnt grass, you may see a yellow or brown patch surrounded by vigorous, healthy grass.
Plants need the sun to survive. There’s also such a thing as too much of a good thing. Excess sun exposure, especially paired with heat or drought, often results in burnt grass.
Grass varieties adapted to full or partial shade may be more susceptible to sun damage. Maintaining an otherwise healthy lawn that receives adequate water will protect against most cases of sun stress.
Fire or Extreme Heat
Burnt grass is sometimes the result of heat or even flame. This can occur naturally — i.e., in the case of wildfire — or in areas containing firepits, grills, or heat-creating equipment. Lawns with deep root systems often survive mild or moderate damage caused by fire or extreme heat.
Fire damage is unique because it affects the grass blades directly. Meanwhile, other causes of burnt grass typically affect the root system.
Seasonal drought is a frequent cause of burnt grass. It can also exacerbate other types of damage, such as fertilizer burn, sun exposure, and extreme heat.
It’s natural for turf grass to go into dormancy during extended periods of drought. More drought-tolerant varieties can withstand several weeks. While the dormant grass will be dry and turn yellow or brown, green blades will emerge when conditions improve. If you’re growing a type of grass not built for dry weather or the situation is particularly extreme, however, the grass may die down to the roots.
Will Burnt Grass Grow Back?
Whether or not burnt grass will grow back depends on the extent of the damage. Grassroots often survive even when the blades are dead or damaged. This is how grass grows back after freezing temperatures or extreme drought.
I recommend fixing the issues that caused the burnt grass and then waiting to see if new growth emerges. This is the best way to determine if the grass is truly dead or not. While it could take some time for your lawn to completely grow back, you should see new growth within a couple of weeks.
Keep in mind that this applies primarily to perennial grasses. Annual grasses are unlikely to return after severe damage caused by drought or fertilizer burn. Unless you know for a fact that your lawn is planted with an annual grass — e.g., in the case of winter overseeding of warm-climate lawns — it’s safe to assume that you’re dealing with a perennial grass variety.
How Do You Fix Burnt Grass
You may be relieved to learn that burnt grass is not necessarily a death sentence for your lawn. In many cases, it’s entirely possible to restore your lawn to its former glory. However, be prepared for the recovery process to take time and a bit of work on your behalf, especially if you want to achieve optimal results.
While each case of burnt grass is unique, these are a few tried-and-true strategies that will start most lawns on the path to recovery:
Dethatch and Aerate
Thatch is a natural layer of dead grass that builds up on the soil over time. You may notice a rapid increase in your lawn’s thatch layer following burn damage that kills the grass blades. A thin layer of thatch can protect the lawn’s roots and prevent things such as soil erosion. However, excess thatch can prevent water and other molecules from reaching the grassroots.
According to the University of Minnesota, grassroots growing in compacted soil is more vulnerable to drought and other stressors. Though compaction is sometimes unavoidable due to soil composition and other factors, aeration is a relatively simple process that can make a big difference in your lawn’s ability to absorb water, oxygen, and key nutrients.
Dethatching, scarifying, and aerating your lawn on a consistent schedule will strengthen the grass and better equip it to resist and recover from burn damage. Personally, I recommend employing these two techniques as ongoing maintenance for the best results.
You may find that burnt grass grows back thinner or in patches. This is to be expected if the root system was partially damaged as well. In my experience, overseeding is typically the fastest and most effective fix.
If the burnt grass was caused by an environmental stressor, consider overseeding with a different grass type that is better suited to such conditions. For example, you may want to overseed with a more drought-resistant grass variety if your burnt lawn was caused by excess sun exposure or dry conditions.
Watering heavily will help flush excess nitrogen from fertilizer or animal urine out of the topsoil. It will also replenish moisture lost from the roots during times of drought or extreme heat.
Understanding when is the best time to water grass, watering deeply and as needed will encourage the strongest, most extensive root system possible. Grass with deep roots is more likely to survive burn damage of all kinds.
Keep in mind that too much water can also do damage. Take into consideration your lawn’s individual needs and the local climate to avoid oversaturating the soil.
How Long For Burnt Dead Grass to Grow Back
After addressing the cause of burnt grass, it can take some time before you see full or even partial recovery.
When top growth dies back, it can take 3 or more weeks for new growth to emerge from the remaining root system. Note that this waiting period generally won’t start until the grass senses it is safe to grow again — i.e. when the initial cause of burn damage is eliminated.
How long you can expect to wait largely depends on the grass variety, the type of damage, as well as how early on the damage was diagnosed and treated. I recommend researching how quickly your specific grass type typically takes to bounce back from the heat and/or drought damage for a general timeline.
Of course, there are some cases where burnt grass is slow to recover or fails to grow back. I highly suggest treating persistent thin or bare areas with fresh grass seed after you’ve addressed the original cause of damage.