If you’re battling stubborn weeds that keep popping up on your driveway, fence lines, or gravel paths, RM43 Weed Killer is your go-to solution. I’ve spent years wrestling with invasive plants, and this product has transformed my approach to weed control.
Its powerful blend of glyphosate and imazapyr not only wipes out existing weeds but also keeps them at bay for up to a year. Trust me, if you want a low-maintenance, weed-free yard, RM43 is worth every penny.
Let’s get into my journey with this herbicide and why it’s a must-have.
My Experience With RM43 Weed Killer
I’ll never forget the summer my gravel driveway turned into a weed jungle.
Dandelions, crabgrass, and some prickly vines I couldn’t even name were taking over, mocking my feeble attempts at hand-pulling and weaker sprays.
I was fed up, and after some research, I stumbled across RM43 Weed Killer.
The reviews were glowing, promising total vegetation control, so I grabbed a gallon from my local Tractor Supply and got to work.
Mixing RM43 was straightforward. I followed the label’s instructions, blending 7.4 ounces of the concentrate with a gallon of water in my pump sprayer. The first thing I noticed was how easy it was to apply.
The solution sprayed evenly, and I targeted my driveway, fence rows, and a patchy area near my barn. Within a couple of days, those pesky weeds started yellowing. By the end of the second week, they were completely dead—roots and all. I was amazed at how thorough it was. No green sprouts poking through, just bare, clean ground.
What really blew me away was the longevity. I sprayed in early summer, and by the following spring, I still had minimal regrowth. Compare that to my old go-to, Roundup, which had me respraying every few months.
RM43’s claim of up to a year of weed prevention wasn’t just hype—it delivered. I also appreciated how rainfast it was. A surprise shower hit a few hours after I sprayed, and it didn’t wash away the effectiveness.
My only hiccup was accidentally overspraying near a rose bush, which didn’t survive. Lesson learned: precision is key with this stuff.
Using RM43 felt like wielding a superpower. It gave me back control over my property, saving me hours of weeding and frustration. But it’s not perfect, and I’ll get into the pros, not-so-great parts, and how to maintain those weed-free zones.
Stick with me—you’ll want to know the full scoop before you spray.
Pros of RM43 Weed Killer
- Long-Lasting Weed Control
RM43’s biggest selling point is its staying power.
Unlike most weed killers that fizzle out after a few weeks, this stuff keeps your treated areas weed-free for up to a year.
I sprayed my gravel path last June, and as of now, in July 2025, I’m still seeing bare ground with only a few stragglers.
The combination of 43.68% glyphosate and 0.78% imazapyr works like a one-two punch: glyphosate kills existing weeds, while imazapyr binds to the soil to prevent new growth. For someone like me who hates repetitive yard work, this longevity is a game-changer.
- Versatile Application
I love how versatile RM43 is. Whether you’re tackling a gravel driveway, fence lines, sidewalks, or even stubborn brush around your barn, this herbicide handles it all. I’ve used it for spot treatments on poison ivy creeping up my fence and for total vegetation control in areas I wanted completely bare.
It’s effective against over 150 types of weeds, from kudzu to thistles, making it a Swiss Army knife for weed control. You can use it with a backpack sprayer, pump sprayer, or even an ATV-mounted sprayer for larger areas, which makes it adaptable to any setup.
- Rainfast and Fast-Acting
One of my biggest gripes with other weed killers was how a sudden rain could ruin my efforts. RM43 is rainfast in just two hours, so you don’t have to obsess over the weather forecast. I sprayed on a cloudy day, and when it rained later, the weeds still bit the dust. Plus, it’s quick to show results.
Within 48 hours, I saw wilting, and by two weeks, everything was brown and crispy. This speed is a huge win when you’re eager to reclaim your space from invasive plants.
- Cost-Effective for Large Areas
At first, I balked at the price—around $80-$100 for a gallon. But when you break it down, RM43 is a steal. One gallon treats up to 17,297 square feet, which is enough for my driveway, fence lines, and more.
I mixed 7.4 ounces per 1,000 square feet, and a single jug lasted me multiple applications. Compared to hiring a landscaper or buying weaker products that need constant reapplication, RM43 saves you money in the long run. It’s like investing in a quality tool that pays off over time.
- Safe for Pets and People After Drying
As a pet owner, I was relieved to learn that once RM43 dries, there are no entry restrictions for pets or people. My dog loves roaming the yard, and I didn’t have to worry about him getting sick after I sprayed.
The label emphasizes keeping pets and kids out during application, but once it’s dry, you’re good to go. This peace of mind is huge, especially if you’ve got a busy household like mine.
Not-So-Good Parts of RM43 Weed Killer
- Non-Selective Powerhouse
RM43 doesn’t discriminate—it kills everything it touches.
While that’s great for clearing out unwanted vegetation, it’s a nightmare if you accidentally hit your prized plants.
I learned this the hard way when I got careless near my rose bush.
The label warns against spraying over the root systems of desirable plants, and they mean it. Imazapyr can translocate through roots, so even a little drift can spell disaster.
If you’re working near gardens or trees, you’ll need to be surgical with your sprayer.
- Pricey Upfront Cost
Let’s be real: RM43 isn’t cheap. A gallon runs about $80-$100, and for small yards or tight budgets, that can sting. I justified it because of the coverage and longevity, but if you’re only treating a tiny patio, you might hesitate.
There are cheaper alternatives like Roundup, but they often require more frequent applications, which can add up. Still, the initial cost might make you pause if you’re not tackling a large area.
- Windy Days Are a No-Go
Applying RM43 on a windy day is asking for trouble. I made the mistake of spraying on a breezy afternoon, and some drift hit a patch of grass I wanted to keep. The label stresses calm conditions, and I get why.
Wind can carry the spray to unintended areas, killing plants you didn’t mean to target. It’s not a dealbreaker, but it means you’ll need to plan your spraying days carefully, which can be a hassle if your schedule is tight.
- Soil Sterility Concerns
RM43’s imazapyr component binds to the soil, preventing new growth for up to a year. That’s awesome for driveways but problematic if you change your mind and want to plant something later. I sprayed an area I thought I’d keep bare, then decided to plant grass seed a few months later—big mistake.
Nothing grew. If you’re using RM43, commit to keeping the area vegetation-free for a while, or you’ll be waiting a long time to replant.
Tips For Using RM43 Weed Killer
- Plan Your Application Carefully
Before you even open the jug, map out exactly where you want to spray. RM43 is a total vegetation killer, so you need to be crystal clear about where you want bare ground. I walk my property with a notebook, marking areas like driveways and fence lines while steering clear of gardens or trees.
Check the weather, too—pick a calm, dry day with no rain for at least two hours. I like early mornings when it’s cooler and less windy, ensuring the spray stays where I want it.
- Mix Precisely and Clean Up Thoroughly
Mixing RM43 is simple, but precision matters. Use 7.4 ounces per gallon of water for spot treatments or 6 ounces for woody plants, and always measure carefully. I use a marked measuring cup to avoid guesswork.
After spraying, clean your equipment immediately. I rinse my sprayer with water and a bit of dish soap to prevent residue buildup, which could clog it or accidentally spread herbicide later. Also, wash any protective gear like gloves or goggles to avoid skin irritation.
- Protect Nearby Plants
To avoid collateral damage, shield desirable plants. I use cardboard or plastic sheets to cover nearby shrubs or grass when spraying. If you’re working near trees, keep the spray away from their root zones—imazapyr can travel through soil and harm them.
I also apply RM43 in a low-pressure, targeted stream rather than a wide mist to minimize drift. If you’re super cautious, consider spot-treating with a small sprayer instead of broadcasting over large areas.
- Monitor and Spot-Treat Regrowth
While RM43 can keep weeds at bay for up to a year, some stubborn ones might sneak through, especially in high-traffic areas. I check my treated zones every couple of months and hit any new sprouts with a diluted RM43 mix.
For small regrowth, I use a handheld sprayer with a 4-ounce-per-gallon mix to save product. Regular monitoring keeps your property looking pristine without needing a full reapplication.
- Store Properly for Longevity
RM43’s concentrate has a solid shelf life if stored right. I keep mine in a cool, dry shed away from direct sunlight and freezing temperatures. Make sure the cap is tight to prevent leaks, and never store it near food or pet supplies.
I also label the jug clearly to avoid mix-ups. Proper storage means you can use it over multiple seasons, maximizing your investment.
Comparing RM43 To Other Weed Killers
I’ve put RM43 to the test against Ortho GroundClear, MENARDS Weed & Feed, and Deadweed Brew. Each product has its place, but here’s how they stack up head-to-head across key factors to help you choose the best for your weed woes.
RM43 Vs. Ortho GroundClear
- Weed-Killing Power: RM43’s 43.68% glyphosate and 0.78% imazapyr combo obliterates over 150 weed types, from dandelions to poison ivy, with root-deep kills in two weeks. Ortho GroundClear, with 5% glyphosate and 0.08% imazapyr, is effective but less potent, struggling with tougher vines. I cleared my driveway with RM43 and saw no regrowth for months; GroundClear needed a follow-up spray by late summer.
- Longevity: RM43 prevents weed growth for up to a year—my gravel path stayed bare from June to spring. GroundClear’s residual effect lasts about three months, fine for small areas but not for long-term control. RM43’s imazapyr edge makes it the clear winner for sustained results.
- Cost and Coverage: A $80-$100 gallon of RM43 covers 17,297 square feet, ideal for large areas. Ortho’s 32-ounce concentrate ($25) treats 4,000 square feet, making it pricier per square foot. For my fence lines, RM43 was more economical over time.
- Application Ease: RM43 requires mixing (7.4 ounces per gallon) but sprays smoothly with a pump sprayer. GroundClear’s ready-to-use option is convenient for small jobs, but its concentrate needs mixing too. RM43’s versatility with various sprayers suits bigger projects better.
- Safety: Both are safe for pets once dry (two hours), but RM43’s higher imazapyr demands extra care near desirable plants. I lost a patch of grass to RM43 drift, something GroundClear’s lower potency avoids. RM43 needs more precision but reduces overall chemical use due to longevity.
RM43 Vs. MENARDS Weed & Feed
- Weed-Killing Power: RM43 wipes out all vegetation, perfect for bare-ground areas like driveways. MENARDS Weed & Feed, with herbicide and fertilizer, targets lawn weeds but struggles with broadleaf varieties and isn’t suited for total control. My lawn stayed patchy with MENARDS; RM43 cleared my gravel path completely.
- Longevity: RM43’s year-long prevention kept my driveway weed-free. MENARDS requires monthly applications for lawn maintenance, offering no long-term barrier. For non-lawn areas, RM43 is far superior.
- Cost and Coverage: RM43’s gallon covers vast areas for $80-$100. MENARDS’ $15 20-pound bag treats lawns but not bare ground, and frequent applications add up. RM43 saved me money on my large property.
- Application Ease: RM43’s liquid spray is precise with a sprayer. MENARDS’ granular formula needs a spreader, which I found messier and less effective for non-lawn zones. RM43 was easier for my needs.
- Safety: RM43 is pet-safe post-drying but kills all plants. MENARDS is lawn-safe but risks waterway pollution if overused. RM43’s targeted use was safer for my non-lawn areas.
RM43 Vs. Deadweed Brew
- Weed-Killing Power: RM43 kills weeds to the root, handling tough plants like kudzu. Deadweed Brew, a natural vinegar and clove oil mix, scorches weeds in hours but leaves roots intact, leading to regrowth. My fence line stayed clear with RM43, while Deadweed Brew needed reapplication.
- Longevity: RM43’s imazapyr prevents weeds for a year. Deadweed Brew has no residual effect—weeds returned in weeks. RM43 is the go-to for lasting results.
- Cost and Coverage: RM43’s gallon ($80-$100) covers 17,297 square feet. Deadweed Brew’s $30 1-gallon ready-to-use jug treats 1,000 square feet and requires frequent use. RM43 is more cost-effective for big jobs.
- Application Ease: RM43 needs mixing but works with various sprayers. Deadweed Brew’s ready-to-use spray is simple but depletes fast. RM43’s flexibility suits larger areas better.
- Safety: Both are pet-safe once dry, but Deadweed Brew’s natural formula is gentler on the environment. RM43’s potency requires careful application but uses less product overall due to its longevity.
Frequently Asked Questions (FAQ)
Yes, RM43 is generally stronger than standard Roundup. While both contain glyphosate (RM43 at 43.68%, Roundup typically at 41%), RM43’s addition of 0.78% imazapyr gives it pre-emergent power, preventing weed growth for up to a year. Roundup kills existing weeds but doesn’t stop new ones long-term, so RM43 is more effective for sustained control in non-crop areas.
For spot treatments, mix 7.4 fluid ounces of RM43 concentrate with 1 to 10 gallons of water to cover 1,000 square feet. For woody plants, use 6 ounces per gallon. Always measure precisely and follow the label to ensure effective application without wasting product.
RM43 is one of the strongest weed killers available for consumer use, thanks to its 43.68% glyphosate and 0.78% imazapyr combo. It’s tough to beat for total vegetation control. Other strong contenders include commercial-grade herbicides like Pramitol, but they often require special licensing. For home use, RM43’s potency and longevity make it a top choice.
Once RM43 has dried—typically within two hours after application—it’s safe for pets and people to enter the treated area. I keep my dog away during spraying and until the product is fully dry to be extra cautious, but there are no entry restrictions after that, per the label.
Wrapping Up
If you’re tired of weeds taking over your property, RM43 Weed Killer is the ultimate weapon to reclaim your space. Its powerful, long-lasting formula saved me countless hours of weeding, delivering a clean, bare landscape that stayed weed-free for months.
From driveways to fence lines, this herbicide tackles it all with ease. Just be careful around desirable plants and follow the instructions. For anyone serious about weed control, RM43 is a worthy investment that delivers results you can see and trust.