Spring has sprung—and so have the weeds. They’re pushing through driveway gravel, popping up in sidewalk cracks, creeping across the lawn, and naturally settling into garden beds.
Ah, but what is a weed, anyway? “A plant whose virtues have not yet been discovered?” Or simply a plant growing where you don’t want it? However you define them, weeds are part of every landscape, and many homeowners reach for chemicals to get rid of them.
But be aware. There has recently been a major change in the herbicide aisle: The Roundup that you once knew isn’t the same weed killer it once was.
For the homeowner, Roundup with glyphosate is gone.
The “new” replacement Roundup products are chemical cocktails of fast burn-down herbicides, growth regulators, and long-lasting soil residuals that behave very differently — and can quietly affect nearby plants, soil, and future planting plans if you’re not careful.
A Quick Look at Roundup’s Rise
The original Roundup product was launched in 1974 by Monsanto, using glyphosate, a systemic, non-selective herbicide that moved through the plant, killing roots and all. It quickly became one of the most widely used weed killers in the world.
In the 1990s, with the introduction of bioengineered Roundup Ready crops for agricultural use, the application of Roundup in food crops greatly expanded. Farmers could plant herbicide-resistant crops like soybeans and corn, enabling them to kill weeds without harming their crops.
When Roundup’s patent expired in 2000, generic versions of the herbicide flooded store shelves, making the product even more widely available to homeowners.
Changing Opinions and a Legal Storm
Glyphosate was used everywhere to control weeds: from backyards to golf courses and large corporate farms. But opinions on the product’s safety began to change in the mid-2000s:
- In 2015, the World Health Organization (WHO) classified glyphosate as a possible carcinogen.
- In 2016-2018, Bayer bought Monsanto for $63 billion and took on all its litigation.
- In 2018, a jury awarded $289 million to a plaintiff who blamed Roundup for causing cancer.
- In 2020, Bayer offered $11 billion in global settlements, and in the following years, litigation, trials, and settlements have continued.
In 2023, Bayer removed glyphosate from its residential (consumer) Roundup products in the United States.
However, Roundup, the glyphosate-based herbicide, remains available for professional and commercial farm use. Generic glyphosate products may still be available for residential use—just not under the Roundup brand name.
Breaking Down Today’s Roundup Products
If you pick up a bottle of Roundup today, it’s important to realize it’s not the same product gardeners have used for decades. Current versions contain different herbicide combinations for quick, targeted weed control.
The result isn’t one simple weed killer but a mixture of ingredients that act very differently in the garden. Some burn foliage quickly, some mimic plant hormones, and others stay active in the soil for weeks or even months.
That means these products can affect nearby plants, soil activity, and even what you’re able to plant in that area later.
Reading and following application instructions has always been important, but it matters even more now. These newer formulas behave differently and can cause unintended damage if misused.
Here’s a look at the most common Roundup products now sold for home landscapes and what they mean for gardeners. Note: none are recommended for use in or around vegetable gardens and edible plants.
The following information is not meant to supersede the pesticide label. The label is the law, and you are responsible for reading it and following those directions.
Roundup Weed & Grass Killer – “Exclusive Formula”
This product is typically marketed for use along driveways, fences, flower beds, and around trees. Unlike the original glyphosate formula, it contains a combination of herbicides designed to target both grasses and broadleaf weeds.
The main active ingredients include fluazifop (which kills grasses), diquat (a fast-acting contact herbicide that burns foliage), and triclopyr, a systemic herbicide that mimics plant growth hormones and targets broadleaf weeds and woody plants.
Diquat provides a quick “burn-down,” meaning weeds appear to die rapidly after spraying. However, triclopyr can move within plant tissue and may persist in soil for one to three months, depending on conditions.
Impact for gardeners: Because triclopyr can move through root zones and affect nearby plants, it should be used cautiously around ornamental shrubs, trees, and perennial beds. Misapplication or drift may cause symptoms such as leaf cupping, twisting, or abnormal growth on nearby plants.
Roundup Dual Action Weed & Grass Killer + 4-Month Preventer
This formulation combines several herbicides, including triclopyr, fluazifop, diquat, and imazapic. The addition of imazapic introduces a different type of activity—residual soil control.
In addition to killing existing weeds, the product prevents new weeds from germinating for up to four months.
Impact for gardeners: Residual herbicides can remain active in soil long after spraying. Areas treated with this product should not be seeded or planted for several months, and nearby desirable plants may be affected if the product moves through the soil or root zones. Sensitive crops—including many in the mustard family such as cabbage, broccoli, and kale—can be particularly vulnerable to residual effects.
For that reason, this product is typically best suited for hardscape areas, such as gravel paths, sidewalks, or fence lines, rather than areas near vegetable gardens or planting beds.
Roundup for Lawns
Roundup for Lawns is formulated differently from the other products and is designed to kill broadleaf weeds without harming turfgrass.
These products contain combinations of selective herbicides, including MCPA, quinclorac, dicamba, and sulfentrazone. Each targets specific types of weeds commonly found in lawns, including crabgrass, clover, and dandelions.
Some of these ingredients may remain active in soil for several weeks, and dicamba is known to be volatile under warm conditions, which increases the risk of drift.
Impact for gardeners: Roundup for Lawns can be effective when used as a spot treatment in turfgrass, but it should be applied carefully. Drift from lawn treatments can damage nearby garden plants, and soil activity from some ingredients may affect sensitive plants growing close to treated areas.
Understanding what’s in these products is only half the story—the real question is how gardeners should respond.
The Smart Gardener Takeaway
Today’s Roundup products differ significantly from previous Roundup product, and understanding how these new formulas work is crucial. Using Roundup weed killer now requires careful label reading – it’s not as straightforward as before.
Each formulation works differently, so selecting the right product for the task is important. Use it where it is appropriate—mainly on hardscape surfaces like driveways or gravel paths—and avoid applying these herbicides near food crops, flower beds, and trees.
Weeds are a natural part of gardening. Sometimes you need to bring in the “big guns” to knock back a serious problem, but there are also many ways to control weeds without chemicals. Mulching to cover bare soil, planting dense ground covers, and good old-fashioned hand pulling can go a long way toward keeping weeds manageable in the garden.
Read the label and choose wisely—because in the garden, healthy soil is always the most valuable thing you grow.
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