Best weed killer for large areas

7 Best Weed Killer For Large Areas: Clearing Up A Massive Garden

If you let them get out of control, weeds can destroy your land. In fact, weeds can account for a massive 32% of crop yield losses per year.

If you want to protect your land from these nasty pests then you’ll need to invest in a high-quality weed killer. However, there are tons of products on the market, and it can be difficult to find an effective herbicide that can cover large areas.

In this guide, we aim to provide a comprehensive description of everything you need to know when it comes to eliminating weeds on a larger scale. This guide will contain a list of the best weed killers for large areas as well as a quick subsection on factors that need to be considered if you want to buy a weed killer that’s ideal for you.

If you’re sick of weeds taking over your garden, then read on. We’re about to show you everything you can do to deal with the problem.

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Quali-Pro Prodiamine 65 WDG weed killer

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The 7 Best Weed Killers For Large Areas

Many of these products are ‘all-rounders’ and can work for a variety of different situations. If you’re looking for a comprehensive overview of the most effective large-scale weed killers, then you’ve come to the right place.

Prodiamine 65 WDG

Quali-Pro is a pre-emergent herbicide that is best for pre-emergent grass and broadleaf weeds. This means that its main function is to prevent weeds from growing in the first place. As a result, it cannot be used on areas that already have an overgrowth of weeds present; the ground must be cleared and prepared prior to application.

Quali-Pro Prodiamine 65 WDG Pre-Emergent Herbicide

This weed killer can be used during the spring and fall seasons. It comes in powder form and is stored in a five-pound bottle. Since it comes as a powder, take note that it needs to be mixed with water and applied with a spray. The instructions on the precise measurements that you should take are conveniently placed on the label.

One advantage of investing in powder-form herbicides is that they do not need to be applied with a surfactant. Surfactants are meant to even the application of a liquid on the surface of the soil; however, since surface tension does not apply to granular products, they are not always necessary.

The active ingredient found in Quali-Pro is 65% Prodiamine. This chemical is broken down by microbes in the soil, which are only active at higher temperatures. To make the most out of every application, it is recommended that Quali-Pro is applied when ground temperatures are around 40 to 45 degrees; as a result, it will carry over and continue to be effective once the ground reaches around 55 degrees. This is the ideal temperature for crabgrass seeds and other weeds to start growing.

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From then on, once the crabgrass and other seeds start germinating, the Prodiamine ingredient stops the roots from progressing. This way, it kills the plant before it breaks through the soil.

Overall, Quali-Pro is a reliable herbicide that you can use for fields that have already been prepared for application. Pre-emergent herbicides are crucial for nipping the root of a weed in the bud, lessening the number of times you will have to apply weed killers in the long term.

Tenacity Turf Herbicide

Tenacity Turf can be used as both a pre-emergent and a post-emergent herbicide. There is no need to buy a separate weed killer for either purpose when Tenacity Turf can cover both needs.

Syngenta Tenacity Turf Herbicide

Take note, that it will often take multiple applications and a few weeks for this chemical to really get to the root of the weed problem. Some users report being satisfied with the progress after three applications, administered every two weeks. To keep the chemical in the soil, it is important to invest in a surfactant; in a pinch, a squirt of baby shampoo or liquid dishwashing soap will do the trick.

The active ingredient in Tenacity Turf is 40% mesotrione. This chemical stops a compound that is important for photosynthesis in bottlebrush plants; as a result, it stops growing and dies. This explains why this product doesn’t provide results that are as immediate and as devastating as other herbicides.

On that note, you should always use a heavy rake or a dethatching rake to remove any bentgrass before the first and subsequent applications. This ensures that the chemical is as close to the weed as possible and that it removes any dead stolons as it is being administered.

This 8-ounce bottle can create roughly sixty gallons of herbicide. This means that the cost of its application translates to around a buck per gallon, which is a solid long term investment for anyone that has large areas to treat.

When it comes to shelf life, Tenacity Turf can still be used around five to eight years after its date of manufacture. To make sure that it lasts as long as possible, store it in a cool and dry place.

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One nuance to using a mesotrione-heavy herbicide is that measurements and directions need to be followed closely. This is because they are specific to the weed that needs to be treated. For example, bentgrass and nimbleweed are best treated with three diluted applications instead of just two strong ones because of the vicious stolons that bentgrass is capable of producing.

An advantage of using the Tenacity Turf is that it is possible to overseed immediately after the last application. New seedlings will no longer have to compete with seeds from weeds and other unwanted plants; and in addition, they will not be affected by the herbicide.

RoundUp Concentrate Max Control 365 Vegetation Killer

The RoundUp Concentrate is part of a series of herbicides, several of which have made it to this list. This specific line of product specializes in covering areas that are covered in another material, such as gravel, driveways, patios, walkways, fencelines, and along foundations.

Roundup Concentrate Max Control 365 Vegetation Killer

It is a good option for people who are looking for detailed weed control. The product comes with a wand that releases a small stream of product. Its design is ideal for users who need to spray weeds that are in close proximity to flowers and other vegetation because it helps with aim.

While this is great for small-scale weeding, its battery-powered wand can also be adjusted to let out a diffused stream for broader coverage. It may specialize in weeds creeping up from underneath concrete and cement, but it is still capable of handling large swathes of land.

It is important to be patient with the Roundup Concentrate. In the worst-case scenario, weeds may remain green for about a week before they curl up and die. After this, the ground is sterilized for several months, with only minor touch-ups needed to continue maintaining a healthy area.

Since the RoundUp Concentrate may take some time to unleash its full power, it is recommended to be extra careful during application. Terrain features, such as rocks and slight slopes, may cause the solution to drain to certain parts of the land, the effects of which will only be discovered a little later on.

A 32-ounce Roundup Concentrate bottle will produce over 5.34 gallons of solution. If only six ounces are needed for every gallon of water, then the quart size can produce a little over five gallons of herbicide.

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One issue with this weed killer was that replacement wands are a little pricey. However, considering the versatility of the wand when it comes to coverage, it is understandable.

Overall, the Roundup Concentrate is best for users who need a herbicide that can cover large areas yet delve deep into nooks and crevices as well. As observed in its marketing, there is also an emphasis on controlling weed growth for an extended period of time. The wand sprayer that this product comes with may be better suited for small-scale treatment, so be prepared with a different applicator just in case.

RoundUp Weed and Grass Killer Super Concentrate

The second Roundup product to make it to this list is the Super Concentrate. This line is marketed as the most economical decision for a pre-emergent and post-emergent herbicide.

Roundup Weed and Grass Killer Super Concentrate

Its main ingredient consists of 50% glyphosate and isopropylamine salt. Glyphosate can inhibit the growth of several kinds of plants by inhibiting the progress of a certain plant enzyme. With that said, it is important to administer this weed killer away from any flowers or vegetation.

It is mostly advertised as a post-emergent herbicide; however, it is just as effective as a pre-emergent as well. It is reported to have positive results on freshly renovated lawns. In addition, the product should be applied to fields while users are in protective gear, as the chemical is a potential skin irritant. It is toxic to both people and animals, so ensure that any pets or livestock are well out of the way before beginning application.

Users report weed-free yards for around four weeks before reapplication is needed. The solution can be made by mixing 1.5 ounces in a gallon of water. While it is marketed to make up to twenty-three gallons of solution, some tend to up the dosage to two ounces. Make sure to increase dosage with care, as too much product may leak into the surrounding vegetation. Also, note that its main ingredient is indiscriminate and will destroy any plant that it touches.

One advantage of the Roundup Super Concentrate is that it is waterproof after just half an hour. This is because it has already reached the minimum amount of time required to penetrate into the leaves of a plant. Regardless of whether it rains or there is a need to start watering plants, it will not wash away the solution.

The first signs of the chemical working are evident in two to four days when they begin to wilt. It will take another week or two to thoroughly destroy the weeds.

In sum, the Roundup Super Concentrate is one of the most affordable options on the list for gardeners and farmers who need a solution for tough weeds. It is a strong chemical and a small amount can go a long way.

ROOTX – The Root Intrusion Solution

People rarely think of weeds infesting their pipes until it is too late. The reality is that weeds often grow in sewer pipes because it is an ideal environment for them.

ROOTX - The Root Intrusion Solution

Rootx is a large-scale herbicide that is specifically towards weeds that have crawled into pipes and sewage lines. This product is fantastic and is well regarded in the industry, but before we get into that we need to discuss proper usage. Users have reported that the instructions are a little unclear, so here is an overview of what to do with this product:

This four-pound container has two different compartments. Users need to scoop out and mix half of the contents from each compartment and mix it in a separate container. After that, it is recommended to fill up a separate bucket with five gallons of water.

Once this is complete, take the mixture to the toilet that is nearest to the local drain line’s exit and flush it. Immediately begin pouring the RootX powder mixture directly into the center of the bowl so that it flows away, then top it up by pouring the extra bucket of water down for good measure. The extra bucket is to ensure that the powder starts expanding in the pipelines, where it will do most of the heavy work.

After that’s done, the powder leaves residue all over the inside of the sewer line. This allows it to continue inhibiting the growth of roots and new weeds for an extended period of time.

There are not a lot of products out there that cater specifically to large-scale maintenance of sewage lines and pipes, so having some RootX on hand to clear out overgrowth is a huge advantage. RootX also sells a funnel for mixing the powders more thoroughly. While it is not a necessary purchase, it may be a worthwhile investment for people who need to conduct multiple treatments on their drains.

Roundup Pro Weed Killer Concentrate

This product is formulated to take on large, industrial-scale areas for the complete removal of any type of plant. It is a post-emergent herbicide that is capable of covering around 435,600 square feet. This is the product marketed for treating construction sites, golf courses, farms, and other vast areas.

Roundup Pro Weed Killer Concentrate

It has the same main ingredient as the other Roundup products mentioned previously on the list. The 50.2% glyphosate liquid is indiscriminate and will remove any plant that it comes into contact with. Since this chemical is harmful to all sorts of living creatures, it is strongly recommended that the solution is applied in full protective equipment (which includes rubber gloves, long pants, and a long-sleeve shirt), with pets and other livestock kept well out of the way.

The Roundup Pro is best applied with a tank sprayer. However, this is sold separately. Most users encourage this additional investment because it makes application easier, considering that this is most likely going to be used over a large area.

Due to its concentration, the solution can stain other materials such as hardscape surfaces. The strength of the mixture can also seep into other areas and affect the quality of the soil. Make sure to closely follow the measurements indicated on the label to avoid mixing too much at any given time.

One challenge to buying the Roundup Pro is managing the amount that is given before the expiration period. This comes in packs of 2.5 gallons of concentrated herbicide. That’s a lot of herbicide to go through in a short amount of time.

It is mainly marketed as a post-emergent herbicide and it does a great job of destroying anything that it comes into contact with. The Roundup Pro does its best job moving through foliage. However, some users have also reported success with using it as a pre-emergent, since it is soluble enough to sink into the soil and exterminate any unwanted seed pods that are germinating.

Overall, the Roundup Pro is a solid option for those who are looking for an herbicide that can handle industrial applications.

RoundUp QuikPro

The QuikPro is the most recent herbicide developed by Roundup. It is another indiscriminate herbicide, which completely destroys any plant that it comes across. The active ingredient, 73.3% glyphosate, achieves this by disabling the plant’s capacity to absorb nutrients from the soil.

Roundup QuikProOne massive benefit of the QuikPro is that it does not affect the quality of the soil. As a result, users are free to reseed the area after treatment is complete. The disadvantage to this is that the occasional weed will continue to pop up since it does not completely sterilize the soil. However, this is a small price to pay for the ability to continue using the land for planting.

This herbicide comes in granular form and is mixed into water to create the treatment. The company recommends mixing 1.5 ounces of the product into a gallon of water; however, some users have reported upping the dosage to two ounces with excellent results. If the company’s recommendation is followed, then the product can produce over 72 gallons of solution.

The key ingredient to the speed and efficiency of the QuikPro’s work is the 9.3% diquat dibromide. This is a fast-acting herbicide that supplements the work of the glyphosate, immediately injuring plants that it comes in direct contact with. Since it is a moderately toxic chemical, it’s not the main ingredient in the formula.

The dual formulation is incredibly effective in killing both the top of the weed as well as its underlying root system. With that said, it’s important for users to be decked out in full protective gear before applying this herbicide. This lowers the risk of skin irritation and other health risks. Pets, livestock, and children need to be away from the area as it is being treated.

Even if it’s effective at targeting the entire weed, it is still recommended to start applying it on plants and grasses that have been cut down to a medium height at roughly around two inches for the leaves to still have space to absorb the chemical. This is because its burn time is quick and it may not be able to reach the entire root system for long lawns or tall weeds.

The biggest difference between the QuikPro and the rest of the products is its speed. If you’re short on time, then this is the best choice by far.

What To Consider When Looking For The Best Weed Killer For Large Areas

While the products on this list are the best in what they do, each one has a distinct set of characteristics that define how they address problems with overgrowth. Here are some considerations that need to be made before buying an herbicide.

  • Whether It Is Safe For Other Living Beings

If the area being treated is near to neighborhoods or livestock, then it’s important to consider the active ingredients being used as well as any lingering effects that the solution may have on the area. Tons of weed killers have high quantities of potentially toxic chemicals, which poses a health hazard to those with compromised immune systems. These effects are not lethal, but it can lead to illness under prolonged exposure. Before anything else, the safety of other living beings within the vicinity comes first.

  • Whether You Need It For Prevention Or For Cure

Pre-emergent herbicides are applied to keep an area free of weeds, while post-emergent herbicides kill weeds that already exist.

It is important to establish whether you want to prepare the land to prevent the growth of weeds or whether you are planning to kill weeds that are already present. This is because certain herbicides are formulated to work in one way; while other herbicides are capable of doing both. Budget constraints may also be an issue and so it is best to look through the options that best suit your requirements.

  • Where It Will Be Applied

Not all weeds are the same. Some grow on grassy areas, while others creep up slowly on hardscape. It is best to find a weed killer that can target the root of the problem while keeping certain areas protected. Most brands on the list are indiscriminate and will kill any plants it comes into contact with, so ensure that the area for application has been separated. The equipment used in administering the solution can also be a big factor in keeping flowers and surrounding vegetation safe.

  • What Weather Conditions It Will Be Applied Under

Herbicides could come in either granular form or liquid form; their main ingredient may also differ. These considerations need to be made because it affects the way that the herbicides activate. Some may need time to seep into the ground before they work, while others are activated under the heat. It is important to keep the weather or season in mind to ensure that the solution does not get washed off or deactivated before it even begins to take effect.

  • Why You Need To Treat The Area

Maybe the area needs to be prepared for a construction site, or maybe it’s being maintained for a golf course. Regardless of the circumstance, you need to pick the product to suit your situation. Some areas will experience heavy foot traffic and will need an herbicide that can do the job without endangering the people nearby.


This is far from being a conclusive guide that covers every aspect of weeding. However, it is a solid starting point for anyone who wants to learn how to deal with these unwanted plants on a larger scale.

Buying the right weed killer can save you time, money, and a lot of frustration. If you can educate yourself on how to work with herbicides, there should be no need to rely on a third-party service provider to do the job for you. You also won’t need to waste money on cheap or ineffective products.

Finally, before you go out and buy a herbicide always remember two things. One, careful application and maintenance is key to getting the best results. Two, once you get around to using your product; always make sure to follow directions, wear protective equipment, and use the herbicide appropriate for the area.

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