RM43 vs Roundup (Which One to Pick)

Non-selective herbicides are a great solution for clearing up any form of unwanted plants. And if that’s what you’re looking for, you have two great options — RM43 and Roundup. 

The RM43 is the better choice in the RM43 vs Roundup battle.

RM43 has Glyphosate, isopropylamine, and polyethoxylated tallow amine as active ingredients but Roundup only contains Glyphosate and Imazapyr. So, RM43 is much stronger than Roundup in restricting the growth of the treated soil.   

There are other differences as well. So, let’s dig up some more dirt about the two non-selective herbicides and help you choose the best one!

RM43 vs Roundup: Head-to-Head Comparison

Both RM43 and Roundup do a great job cleaning up unwanted weeds and plants from the soil. Many find them identical to an extent. That leads us to question, Is RM43 the same as Roundup?

Well, no, RM43 isn’t the same as Roundup. Although both are non-selective herbicides in nature, the presence of active ingredients makes their output different. For example, they differ in regrowth prevention, effectiveness, safety issues, mixing ratios, and areas of application. 

You’ll get to explore these differences from the side-by-side comparison table given below: 

Factors RM43 Roundup
Active Ingredients Glyphosate (43.68%), Imazapyr Glyphosate (41%)
Herbicide Type Non-selective  Non-selective 
Regrowth Prevention 12 months N/A
Effectivity  Both Pre-emergent and post-emergent herbicide Post-emergent herbicide
Safety Hazardous Relatively safer
Mix Ratio 6 oz per gallon 2.5 oz per gallon 
Area of Application Gravel paths, Driveways, Fences, Drainage areas Garden, Lawns
Cost Budget-friendly Expensive

Factor 1: Active Ingredients

Having Glyphosate as the core active ingredient, RM43 contains around 2.68% more Glyphosate than Roundup. Moreover, Imazapyr also acts as an active ingredient in RM43 which Roundup doesn’t have. 

Now, the presence of Imazapyr is what helps RM43 leave a lasting effect on the treated area. It’s an essential ingredient that works to stump weed growth. 

Getting into the details, RM43 is made up of herbicide ingredients like Glyphosate (43.68%) and ImazapyR. Other ingredients make up 55.54% of RM43.

On the contrary, the chemical composition of Roundup consists of glyphosate (41%), related organic acids of glyphosate (1.5%), isopropylamine (0.5%), polyethoxylated tallow amine surfactant (15.4%), and water (41.6%).


Source: roundup.com

Factor 2: Effectiveness

Roundup weed killer acts as a post-emergent herbicide, while RM43 acts as both post-emergent and pre-emergent herbicide. 

RM43 effectively eliminates stubborn weeds and keeps them from returning for up to a year! It takes a few weeks for RM43 to clear out the existing weeds. 

In comparison, Roundup is proficient at taking out various types of weeds and grass, much like RM43. However, it lacks the ability to stop new plants from sprouting in the treated area. 

But on the bright side, Roundup acts faster than RM43 and kills weed within 2-4 days of application. 

While Roundup is excellent for getting rid of existing weeds, it doesn’t offer the long-term prevention that RM43 does.

So, RM43 is your go-to choice for keeping weeds at bay for an extended period. 

On the other hand, Roundup is better for clearing out weeds and grass. Especially if you plan to plant something new in that spot.

Factor 3: Best Use

RM43 is the perfect herbicide for locations where you don’t want weeds to grow out. Roundup, on the other hand, is an ideal herbicide if you plan to replant the area afterward.

Locations like gravel paths and driveways are the best spots to use RM43. Apart from that, RM43 can also help to prevent weed growth in seams between pavers and concrete.

It helps in clearing weeds and brush near fences and drainage areas.

With Roundup, you can clear overgrown areas of weeds before planting a garden, grass seed, or sod. You can also use Roundup to kill the unwanted weeds near the desirable plants.

Roundup allows you to prepare your soil for replanting and reseeding within a few days. So, if you’re preparing the ground for something new, herbicides like Weed B Gone and Roundup are your better choices compared to RM43.

Note: Be cautious when using RM43 near desirable plants as it can drift through watering and harm nearby vegetation. Think of RM43 as a long-term solution for keeping plants away for an extended period.

Factor 4: Application

You need to use about 7.4 fl. oz. RM43 in 1 gallon of water whereas the amount is 2.5 fl. oz. for Roundup. This means you’ll have to use more RM43 than Roundup to get maximum output.

When using RM43 for total vegetation control you need to mix 7.4 fl. oz. of RM43 with 1 to 10 gallons of water. This should help you cover around a 1000sq ft area. You can apply around 2.5 gallons of RM43 total vegetation control per acre per year at max. 

For optimal results, apply it to actively growing weeds during early summer. 

If you’re using RM43 for spot control of brush, vines, and weeds, the process remains quite similar. Employ hand-operated spray equipment, mix 6 oz. of RM43 per 1 gallon of spray solution. You must ensure thorough and uniform coverage of the foliage of woody plants.


Source: facebook.com

 For Roundup, the process varies depending on the task at hand. For general weed control of annuals, you can use a tank sprayer to mix 1.5 fl. oz. (equivalent to 3 tablespoons) of Roundup with 1 gallon of water. 

This mixture is effective for targeting common annual weeds. 

For dealing with stubborn vegetation, the recommended ratio is 2.5 fl. oz. of Roundup per 1 gallon of water. This higher concentration is designed to tackle tougher weeds.

Factor 5: Safety

Both RM43 and Roundup possess almost similar active ingredients. However, the ratio of certain chemical components can end up being more hazardous than the others. 

This might lead users to question, which one is safer. Is RM43 safer than Roundup?

No, RM43 is not safer than Roundup. 

RM43 contains a slightly higher amount of Glyphosate than Roundup which makes it more toxic and hazardous. Usage of Glyphosate is very minimal in both RM43 and Roundup which is deemed safe for use.

However, Glyphosate is also considered a probable human carcinogen that can cause cancer from long exposure.

In fact, the inert ingredients in RM43 and Roundup are even more toxic than glyphosate. These ingredients can amplify the toxic effect on human cells increasing the risk of cancer.

Chronic toxicity tests for imazapyr indicate that it is not carcinogenic, mutagenic, or neurotoxic. 

For trees, the application of RM43 can even kill large and mature trees! It leaves a residual presence in the soil for a long period of time.

This means RM43 can linger and gradually move with water runoff. As it travels, it can harm new plants and grass it encounters by being absorbed through roots.

RM43 is active in the soil and can even harm established plants through their roots. It can drift through the soil, be carried by water, and affect areas beyond where it was initially applied. This means it can unintentionally harm vegetation that was originally outside the treatment area.

In contrast, Roundup doesn’t linger in the soil and doesn’t pose a threat to plants through their roots. 

You should also check out our take on the difference between Grazon and Pasture pro.

So, Is RM43 Better Than Roundup?

Yes, RM43 is better than Roundup. But it actually depends on what you are looking for.

RM43 is much stronger than Roundup due to possessing a higher presence of Glyphosate. This makes RM43 more effective in preventing plant and vegetation regrowth compared to Roundup.

After application, it’s essential to wait for 14 days before reapplying so that they have sufficient time to work. During this period, you should refrain from removing any treated weed growth or vegetation.

Now, where they differ is in long-term weed control. 

RM43 residue leaves lasting impacts on the soil because it contains Imazapyr, an ingredient absent in Roundup. It works to control invasive plants by rapidly photodegrading when applied to water, but not soils.

Imazapyr stays in the ground for up to a year, effectively preventing the growth of new weeds and grass seeds.

So, the RM43 is a better option than Roundup if you want a stronger herbicide that can prevent vegetation regrowth. However, if you’re looking to grow new plants and vegetation on the treated soil, you should go with Roundup. 

Can You Mix RM43 with Roundup?

No, you shouldn’t mix RM43 with Roundup or any other herbicides. It can lead to potent or unexpected chemical reactions. The label for RM43 does not specify any herbicides that can be safely combined with it.

Introducing Roundup or any other additives can potentially change the herbicide’s composition and its effectiveness. 

A mismatch in the mix-ratio of the two herbicides is bound to imbalance the chemical composition of the mixture.


What is the highest strength of glyphosate?

The highest strength of glyphosate is available around 540g. But you will mostly find standard Glyphosate that’s available in 360g

Is Roundup banned?

No, Roundup is not banned. The U.S. Food and Drug Administration permits the use of Roundup in the February 2020 notice. However, there are some restrictions in several states and countries because of cancer concerns related to its ingredient (glyphosate).  

Is glyphosate safe in the rain?

No, Glyphosate is not safe in the rain. The application of glyphosate must be avoided during heavy rain prediction. It can wash off the treated soil and affect surrounding plants.


That concludes our take on RM43 vs Roundup.

You must carefully consider the mix-ratio of the herbicides for a safe and secure application. Be sure to consider the pros and cons of the two herbicides before picking the right one!

Have a good day!