Does Gasoline Kill Grass and Weeds?

In recent years there has been a surge of advancements in electric lawn and garden equipment that has produced battery or outlet-powered machines that run superior or on par with traditional fuel-driven machines.

Almost entirely gone are the days when lawn maintenance requires you to carry a bottle with gasoline inside to top off your weedeaters or other power tools. This is a relief for our lawns, as only a few drops of gasoline can damage your turf.

Key Points:

  • Battery or outlet-powered machines are now a superior alternative to traditional fuel-driven machines.
  • Carrying a bottle of gasoline is no longer necessary for lawn maintenance.
  • Even a few drops of gasoline can damage or kill grass.

Will Gasoline Harm Turf and Weeds?

Even though a few drops of gas will not kill your lawn, there will be immediate and noticeable discoloration to the blades that got exposed to the fuel. More spills and the effects become more pronounced to the point of large areas of dead grass spreading outward.

Add to the fact that a puncture or leak in a fuel line or gasoline tank can lead to large volumes of gas spilling out onto your turf. If this happens, your lawn is in trouble. 

A knocked-over gas can, or a bad spill will kill the grass that was immediately hit by it and any roots that are too exposed in the neighboring area. If the spill is allowed to spread, it will destroy all blades of grass, root systems, and soil microbes in its path.

Letting gasoline sit in the soil will further exacerbate the issues and lead to a lawn that may not be able to be replanted. 

Effects of Gasoline on Plants

While a few drops may not be a big deal, a lot of gas can spell disaster for your lawn. Not only will the ground be damaged, as well as the grass growing in it, but you are also at an increased risk of fire hazards and exposure to toxic fumes. Below are some of the effects on plants when exposed to varying levels of gasoline.

Amount of GasCommon CauseEffect on Plants
A Few DropsFalls off the tip of the gas nozzle at the beginning or end of the pour You may see a slight discoloration on the blades of grass that had direct contact with the fuel but little effects outside of those spots and no residual gasoline damage 
A Cup of GasA full tank overflows and spills onto the grassPlant ins the immediate area of small accidental spills will probably have dead spots and have effects on soil life and health
A Gallon of Gas A knocked-over gas can without anti-spill protection Dead grass in the area due to the direct impact gasoline has and the massive loss of soil microbes 
More than a Gallon of GasA ruptured fuel tank or some other serious issue with a lawn mower or other power tool can cause a massive gasoline spillage Depending on your soil type, all the plants in the affected area will die, and several inches of soil will have to be removed and fresh soil laid back for new grass seed to be able to sprout

How Long for Gas to Breakdown in Soil?

Gas can kill grass in as little as 30 minutes, and takes 1 to 2 years for soil organisms and soil solarization to naturally repair your damaged lawn. Trying to keep a green lawn that has been exposed to gasoline can be hard, and you may need to wait many months to repair your glossy lawn.

The real determining factor of whether it will take hours for gasoline to dissipate or years is how much was spilled and how quickly it was cleaned up. 

However, just a few drops of gasoline falling onto your soil likely will be inert by the time the gasoline smell is gone. A larger spill with residual gasoline that seeps into the soil, especially sandy soil, where it will spread quickly, will damage the soil for a long time.

If you do not have the time to wait for the soil to repair for grass naturally, you can speed things up by removing the contaminated soil and replacing it with fresh soil. 

How to Clean Up a Gasoline Spill?

Depending on the type of soil you have, spills on grass will have to be handled differently. Ideally, you will fill all lawn machines on pavement or another surface where spills can be quickly soaked up. But if your lawn care leads to a spill on grass, you will need to act quickly to reduce the long-term effects and get green grass back.  

In heavy clay soil, you can easily remove the topsoil and the patch of soil directly around the spill. Just getting this out of the way is all it takes, as the gas will not have had. chance to spread far or leech into the soil deeply.

The roots of neighboring grass will not be exposed to the spread of gasoline and will survive. Once the soil holding gas is removed, fresh grass seed can be lead in new soil. 

In loam soil, you will want to act quickly because of the capillary effect of rich soil. You can remove the top layer where the spill happened and let it air out until the smell of gasoline stops. Depending on the volume of gasoline involved in the spill, the soil microbes will be able to break down the hydrocarbons after exposure to gasoline. 

In sandy soil, the entire lawn can become affected if the spill is large and not cleaned up immediately. This type of soil needs to be removed, or the large particles will allow the gas to seep deep down and even potentially enter groundwater sources. You can replace the gas-filled sandy soil type with enriched garden soil that has more microbes and can mitigate the effects of gasoline spills on new grass seeds. 

Does Water Wash Away Gasoline?

If a small amount of gasoline is spilled, then using water to super-dilute it may be all that it takes to eliminate any harmful consequences. If you have a suitable soil type, the gas will wash away and be watered down to the point where it doesn’t harm more turf.

Using water to clean up a gas spill can backfire and lead to more damage if the situation isn’t approached correctly. 

Water can spread the fuel much further than it would go on its own, and if the concentration is still high, burn or kill any plants it spread to. Runoff containing gasoline can enter waterways and harm wildlife or other plants in the area. Water is not as effective as removing the contaminated soil and is likely to create worse problems for a larger area than either leaving the gas or digging up and replacing the soil it has spilled onto.

Either way, gasoline spilled on the lawn will kill your grass.