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Does Diesel Kill Weeds? (9 Things You Should Know)

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If you’re into gardening, or you just want a nice lawn, then you know what a menace weeds are. They’re like a constant adversary in yards and on farms across the country. People have their kids out pulling weeds on summer weekends, and we’re all searching for the best ways to eradicate them for good.

The quest for victory over weeds has people trying all sorts of things. Unfortunately, a lot of the solutions that you can buy online or at your local home and garden store will only go so far. It always seems like we need something stronger to get rid of weeds once and for all.

refilling gas canisters

Some people think using diesel will do the trick. Diesel is, in fact, a very strong substance that will kill weeds, but it probably won’t kill them for good. And, you’re likely going to take out a lot of healthy leaves and even some of your plants if you go around your yard spreading diesel.

Before you start using diesel against your weeds, here are 9 things you should know.

Diesel Will Kill Anything It Touches

Yes, your diesel will kill the weed that’s sticking out of your grass or threatening your tomato plants. It’s a strong fuel that sucks the life out of plants that it touches. That’s great if you’re killing weeds, but most of the time there are other plants around.

If any diesel gets on your plant leaves or other parts of your grass, you can say goodbye for a while. Diesel will kill crops and flowers, so beware.

Diesel Won’t Get to the Seeds

One downside of diesel is that it probably won’t kill the weeds permanently. It will kill anything living, including the roots and stems, but it often leaves the seeds intact.

After a good rainfall, the diesel will be washed away into the groundwater and the seeds will be left there to grow again unimpeded.

You’ll find yourself stuck in a pattern where you have to use diesel over and over again anytime you spot weeds. It may not be worth risking the health of the other plants in your garden.

You Should Limit the Application

Look, we’re not saying diesel won’t work. Putting diesel on the leaves and stems of weeds will make them disappear quickly. We’re just saying that it’s probably not going to be the permanent solution you’re looking for.

Still, some people like to use diesel because they want their yard to look nice and diesel is a quick and effective way to manage appearance.

If you’re going to use diesel, here’s what you should do:

  • Buy a gallon or two of diesel from your local gas station – Make sure to put the diesel you buy in a gas canister and not some random container
  • Using a funnel, pour the diesel into a spray bottle – Use the spray bottle to apply the diesel directly to the weeds doing your best to limit the impacted area.
backpack garden spray

It Can Take a Couple of Days

You’ll usually need to wait around 48 hours for the diesel to work and see the weeds die. You will start to see leaves wilt after just a few hours, but for it to kill the stem, you’ll need a couple of days.

If you don’t get the expected results, then you can try applying more diesel to see if that works.

You Need to Pay Attention to Safety

Anytime you’re handling something like diesel, you need to make sure that you take property safety precautions.

Remember, this is a very flammable substance, and it can be harmful to the environment if not used correctly. Be careful not to leave it in a room where people, especially children, can play with it or breathe in the fumes.

Also, don’t use diesel near any wells or other water sources just to stay safe. Try to spray the diesel on your weeds when winds are low and there isn’t any chance of rain. This will help avoid it from spreading beyond the area you that you are applying it.

Keep Track of How Much You Use

As a best practice, track how much diesel you’re using and how much it takes to kill off weeds. If you’re not getting results with a reasonable amount of fuel, then you may want to move on and try something else that won’t affect the soil or groundwater as much.

Just do this by measuring how much you go through in a spray bottle to kill a grassy weed or any other type of weed in your grass or garden.

Keep Pets Away

We’ve mentioned keeping the diesel away from kids, but you also need to keep a close watch on any diesel on your property in case your dogs or other pets get close.

This also applies to after the diesel is sprayed on the weeds. A curious animal will naturally go up close to the diesel to figure out what that new smell is.

They may try to taste it, and ingesting diesel will be toxic for your animals. If you can, build a barrier around any part of the garden or keep your pets inside for a few hours after you spray the grass.

Talk to Your Local Garden Store Experts

There is plenty of information on killing weeds online. Most of it’s great stuff, but your local home and garden store can be another great resource. They’ll likely have been working there for years helping homeowners and other property owners combat weeds.

Odds are, they’ll know a trick or two that works on your weeds given your local climate and what’s available. They can point you in the right direction or talk to you about how to make the right solution to finally kill those pesky weeds.

metal gas cans for storage

Store the Diesel Safely When You’re Not Using It

Anytime you’ve got fuel or other flammable substance on your property, you need to take precautions when you store it long-term. Unfortunately, a lot of property owners have learned the hard way that diesel needs to be stored in a certain way.

If you’re using diesel to fight weeds, then you’re likely going to be using it regularly because, as mentioned, it won’t get to the seeds.

You’re not going to want to take a trip to the gas station every time you’re ready to kill weeds, so you’re going to need to store it in a shed or somewhere else.

First of all, diesel shouldn’t be kept in the spray bottle. Return any unused diesel to the canister it came from. Also, don’t bring the diesel inside for long-term storage. Keep it in the garage or in a shed to reduce any combustion and fire risk.

The best you can, keep the diesel in a place where there is good ventilation. Without proper ventilation, it can be easier for the fumes to build up and become intoxicating. With good airflow, though, you should be OK.

Final Thoughts

If you’re struggling with weeds in your yard or garden and haven’t had luck with commercial weed killers, feel free to give diesel a try.

Just make sure to stay safe and keep track of your results so you can find the best method for your grass or crops.