In Gardening

Complete Guide on Finding a Strong Weed Killer for your Backyard

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Everybody loves the idea of the perfect lawn and pristine gardens. However, that isn’t always simple because you not only have to keep the right plants growing but also keep the weeds from growing. To do that, you could pull them up one at a time or you can use a strong weed killer.

But even the strongest weed killer on the market isn’t going to work if you don’t use the right one for the weeds you have. Each formula of weed killer is designed to work against a specific type of plant.

What is the Strongest Weed Killer on the Market?

weed killer spray

When you look at the market for weed killers and herbicides, they are divided mainly into two main groups. There are those that work against grasses, including turf grass as well as ornamental grass. Then there are others that are designed to work against broadleaf weeds and brush such as blackberries and thistles.

One thing to remember as you are using weed killers is that when any of them are applied at too high of a rate, they will kill everything. If that’s your goal, awesome. However, if you are spraying thistles in your lawn, you want to be a little bit more careful and apply only as much herbicide as you need.

Glyphosate Weed Killers

Glyphosate makes an incredibly strong weed killer designed to work against grass-type plants. You use these herbicides in your flower beds if your lawn is encroaching. You can also use glyphosate killers on sidewalks to prevent grass from growing in the cracks.

Glyphosate was discovered in 1970 and marketed as RoundUp by 1974


Contrary to common belief, Roundup is not a chemical. It is a brand of products and they make both major types of strong weed killers. However, Roundup is best known for its grassy, glyphosate, weed killers.

You will, at most hardware stores, find Roundup in three different concentrations. There will be ready to use (RTU) formulas that can be put on plants straight from the bottle. 

Concentrated and ultra-concentrated formulas are also available. Be sure to read the label to get the concentration correct when you spray it on your plants to avoid damaging the plants you want to be healthy.

If you are getting Roundup in order to kill grasses near other plants, be sure to buy a Roundup formula that only has glyphosate in it. Again, Roundup makes formulas with other chemicals and you may accidentally buy a broad spectrum strong weed killer that will kill everything.

grassy weeds

Broadleaf Weed Killers

Broadleaf weed killers are designed to work specifically against broadleaf weeds. This class includes dandelions, thistles, blackberries, most woody plants, and briers. Broadleaf weeds are the weeds that homeowners are typically trying to kill, so this is what you should reach for when in doubt.

There are a few major chemicals that are used for the purpose of killing broadleaf weeds. Each has its benefits and plants that it works better on than others. Make sure to read the label to see if the plant you want to kill is listed as a plant the product acts against.

broadleaf weed brambles

2,4-d weed killer

2,4-d is one of the strongest weed killers effective against broadleaf weeds. This chemical acts mainly by causing uncontrollable growth in the cells of the plant. The excessive growth causes the plant to shrivel as it fails to establish proper cell structure and water transport.


Triclopyr is another strong weed killer that works against broadleaf plants and is commonly used in these pesticide formulas. It has a similar function as 2,4-d in that it causes uncontrollable growth in the plants cells.

What Weed Killer Kills Everything

There are times that you feel the need to kill everything, grasses and broadleaf plants. This is commonly done on sidewalks and driveways but also when people are starting landscape projects to create a fresh canvas.

Kill Everything Weed Killer Recipe

Mix together a broadleaf weed killer, grassy weed killer, and a broad spectrum herbicide to quickly and efficiently kill everything. The diquat will kill everything by itself but the other chemicals will keep the weeds at bay for longer.

What is the Fastest Weed Killer

There are two incredibly quick ways to deal with weeds, though both of them will kill everything and not just weeds. The first and fastest weed killer you can use is fire. Don’t light your yard on fire; there are torches that you can buy. While this incredibly fun method is also very effective, some people are a bit nervous using it.

For the fastest spray on herbicide weed killer, you should find diquat. This herbicide breaks down cell membranes so the plant will die within a couple of days. Just be aware that this chemical will work against every plant and not just the ones you want to target.

wilted weeds

How Does a Weed Killer Concentrate Work

You can buy herbicides in ready to use (RTU) containers that you can spray directly onto the weeds but many people prefer to buy a concentrate. Weed killer concentrates will have a specific rate of use depending on the plant you are trying to kill.

To make sure that you get the right amount of the herbicide in the final mixture, they make measuring cups that measure in ounces and even have a pour spout to get it all in the spray bottle.

If you use any weed killer at too high of a rate, it will start to affect plants that you are not targeting. Strong weed killers all have labels stuck to them that will lay out what plants they work against and what concentration to dilute the herbicide to.

What is the Best Time to Use a Weed Killer

gardening weather

A common misconception is that you can spray a weed killer anytime and have it be effective. And it is true that most plants do not like herbicides applied even if they are done at the worst of times. But there are times that are more effective than others.


Make sure that it isn’t going to rain soon when you apply an herbicide. If it rains, the weed killer will be washed off and be less effective. Similarly, you want to apply herbicides when it isn’t too hot or too cold. If it’s a day you would want to garden, it’s a good day to apply an herbicide.

Plant Growth Cycle

One of the best times to apply an herbicide is when the plant is actively growing. All herbicides rely on the chemical being taken up into the plant through the roots or through the leaves. If the plant is not growing quickly, it won’t take up the herbicide quickly either.

Are Natural Weed Killers Effective

With the popularity of organic gardening, you may be looking for a natural, organic weed killer for your garden. Of course, natural weed killers are still chemicals and, while they are not usually that much better for the environment, they don’t usually have bad side effects for people.

Organic weed killers are still made of chemicals

Organic weed killers do take longer to work and they typically have to be applied at fairly high rates. The other issue with organic killers is that they may have to be applied more than once in order to be fully effective.

Strong Natural Weed Killer Options

Salt is an incredibly effective long-term herbicide. It doesn’t do very much against weeds that are already sprouted but it will keep them at bay for a long time and prevent new ones from growing.

Vinegar will help to kill any existing weeds in your garden by changing the pH of the soil to become more acidic. Most plants grow within a specific pH spectrum and by changing that, you will stress them.

Dish soap is useful for helping your natural herbicides stick and spread out. The dampness of it will make the leaves sticky. Dish soap is also a surfactant which will help the chemicals spread out and coat the entire leaf.

Is Weed Killer Dangerous to Pets or Kids

kids and pets

Strong weed killers are very dangerous to kids and pets if they are ingested. If your kids and pets eat them, call the local poison control or go to the emergency room immediately and take the bottle with you.

There are several strong weed killers that will also cause rashes and irritation if they touch the skin. If any weed killer touches the skin or kids or pets, rinse it off as best you can. Read the label on the bottle to see what other first aid may be needed.

Most of the herbicides available will be safe once they are dry for 24 hours. So make sure that kids and pets stay off the area and take your shoes off before you enter the house to prevent any chemicals from getting on their feet.


It can be incredibly annoying to try and keep the weeds contained while still keeping your preferred plants healthy. To do so requires not only strong weed killers but also knowledge on how to use them correctly.