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How effective is RM43? Everything you need to know

If you are in the market for a product that can help you eliminate weeds and prevent them from growing back, without a doubt RM43 is one of the top choices for a good reason.

According to its packaging, it claims to kill all vegetation and prevent them from growing back for at least a year but is this true?

RM43’s main active ingredients include Glyphosate and Imazapyr; When these two are mixed with other supporting ingredients, the concentrate becomes powerful enough to destroy every vegetation they come across

Glyphosate works by inhibiting further production of enzymes required for plant growth, while Imazapyr works by stopping protein production and cell growth hence killing the plant.

How much RM43 should I add to a gallon of water?

RM43 comes as a concentrate, which has not been mixed with water. If you are using it for spot treatment, you will need to mix six ounces of the concentrate in one gallon of water.

On the other hand, if you are spraying a big chunk of land at once, you should mix 7.4 ounces of the concentrate with ten gallons of water for every 1000 square feet.

10 gallons might seem like a lot of water, considering it is just 1000 square feet. However, it is needed to destroy the vegetation from the root up.

How to use RM43 the right way

RM43 has a very long shelf life. One container can last several applications.

Before you begin, make sure you have the necessary PPE equipment such as rubber gloves, boots, overalls, and a gas mask if at all the smell of herbicides affects you.

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Next, you will need a measuring cylinder and lotus of water so you can be able to measure the proper concentrations before you begin spraying.

Remember, if you put more than the required RM43 concentrate, it will take more than a year to dissipate your garden.

As for the spraying equipment, you will need one of the following: a hand-held sprayer such as a pump sprayer, backpack sprayer, or a sprinkler.

For large fields, you might need a machine such as an ATV or a tractor-fixed sprayer.

For great results, use RM43 as explained here:

  • Target the weeds and vines that are starting to develop.
  • If the fruits have already formed, wait until late summer and fall to spray the vegetation.
  • Do not trim or mow the treated plants for at least two months after applying RM43.
  • Only spray RM43 when the weather is sunny, preferably above 60 degrees Fahrenheit. Avoid spraying on windy days as the concentrate may stray and damage perfect plants.

When to use RM43

RM43 acts on grass
RM43 after acting on grass and weeds along a fence. Image: Twitter/RaganAndMassey

RUM43 is both a post-emergent and pre-emergent weed control concentrate. You can apply it before weeds emerge to prevent them from growing or after the weeds have grown to destroy them from the roots.

Though you can use RM43 any season of the year, it is highly effective if used at the beginning of summer or the end of spring, as this is when weeds the weather is conducive for weeds to start growing.

Pros and cons of RM43

Although effective, RM43 has its share of advantages and disadvantages.

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  • It destroys both weeds and undesired vegetation and prevents either of them from growing back for at least a year.
  • It comes at a very competitive price considering a small amount goes a long way, long-lasting effects.
  • Has a long shelf life, and it stays fresh no matter what the conditions of where you store it are like
  • Very simple to mix and use as it comes with comprehensive instructions
  • You can use it in almost every place you may want to control the vegetation
  • It is made of a potent formula that does what it says it will do on the package.


  • It takes at least a week to start showing any significant changes
  • Does not absorb immediately, so you will need to reapply if it rains a few hours after treatment.
  • It can cause many health complications if pets or children happen to ingest it.
  • Many people have complained that the container is poorly sealed; hence it may arrive leaking
  • Since it kills every plant it comes in contact with, it will destroy all your beneficial plants.

Frequently asked questions about RM43

These are the most commonly asked questions about RM43

1. Will RM43 kill large trees?

RM43 will dry up a tree if the roots are not very deep. So it is advisable to keep the solution away from any trees you want to keep.

2. How long before the rains should I apply RM43?

RM43 needs at least a week to be fully absorbed into the internal system of a plant. Therefore, you need to spray it at least one week before the rains.

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Note that if it rains within two hours of application; you will need to reapply the concentrate as the majority of it will have been washed away.

3. Is there a difference between RM18 and RM43?

Yes, there is a difference that lies solely in how they work.

RM18 is sprayed on the leaves and dies down the moment it reaches the soil meaning you can replant on the treated area after a day, whilst RM43 is absorbed until the roots meaning it is a total vegetation control. Its effects last up to a year.

4. Are the results of RM43 instant?

No, the results are not instant. However, you will start seeing a significant change in a few days.

5. What does the 43 on RM43 stand for?

It stands for the 43% percent of Glyphosate found in the concentrate. This percentage is what makes RM43 effective.

6. What type of weeds does RM43 kill?

The packaging can kill up to 150 types of weeds and a few tree stumps. However, it’s imperative to note that it will not work well on drought-stressed weeds.

Final thoughts – Is RM43 really effective?

RM43 is very effective when it comes to vegetation control. It works by destroying any plant it touches, from the leaves to the roots.

Additionally, its effect is long-lasting, and you will not see anything grow back for about a year hence saving you time and resources.