Weed Killer Active Ingredients

weed killer active ingredients header image

The following is a list of the most common active ingredients found in weed killers and what they are best for.

What Makes Weed Killers Work?

List of weed killer active ingredients

Ever find yourself standing in the gardening aisle, weed killer in hand, wondering just what’s inside this bottle promising to reclaim your garden? You’re not alone. The power of weed killers, or herbicides, boils down to their active ingredients – the real MVPs in your battle against unwanted green invaders. These ingredients are scientifically formulated to target and dismantle the unwanted weeds from the root up, ensuring they don’t stand a chance. But it’s not just about eradication, it’s about precision and safety, ensuring that your beloved blooms remain untouched.


330px Glyphosate.svg

Glyphosate is a non selective, systemic weed killer that is used to control a wide range of weeds, grasses, and broad-leaved plants. It is one of the strongest weed killers and is often used on farms and gardens to clear out weeds before planting new crops. Glyphosate is known for its broad-spectrum efficacy and high level of weed control. It is also Rain-fast after application, making it an ideal choice for controlling weeds in areas with frequent rainfall. All these features make it a most effective weed killer and as it kills everything it touches, it is very useful for both gravel driveways and preventing growth on or around artificial grass. Wikipedia

Elixir Gardens is our recommended Glyphosate Weedkiller.

Pelargonic acid

330px Pelargonic acid.svg

Pelargonic acid is a non-selective herbicide that can be used to control a wide range of weeds and grasses. It is a contact weed killer for targeted weed killing, meaning it will kill any foliage it touches, making it great for spot-treatment and spot-control of garden weeds. Pelargonic acid is also biodegradable, non-toxic, and safe for use around pets and humans. Wikipedia

Maleic hydrazide

330px Maleic hydrazide.svg

Maleic hydrazide is a systemic herbicide that is used mainly for selective preemergence weed control in field crops and vegetable crops. It is unique because, unlike other herbicides, it does not kill existing weeds and grasses, but rather prevents the germination of their seeds, so it will prevent weed seeds from ever starting to grow. Maleic hydrazide is also non-residual and will not persist in soil after application, making it a great choice for organic gardening and those looking to reduce their chemical usage. Wikipedia

Neudorff is our recommended Pelargonic Acid and Maleic Hydrazide Weedkiller.



Fluroxypyr is a selective weed killer. It is also one of the systemic weed killers often used for post-emergent weed control in turfgrass (so is often an active ingredient in lawn weed killers), ornamentals, and non-crop areas. It is a powerful weed killer that can control a wide variety of tougher weeds and grasses, such as dandelions, clover, and crabgrass. Fluroxypyr is also rain-fast after applying, making it ideal for protecting food growers with its broad-spectrum weed control. Wikipedia


240px Clopyralid

Clopyralid is a selective systemic herbicide added to lawn weed killers, used primarily for the control of broadleaf weeds in turfgrass and landscape sites. It is one of the selective weed killers known for its exceptional broad-spectrum control, long residual activity, and low toxicity to wildlife. Clopyralid has a low water solubility, making it an ideal choice for areas that are prone to drought. Additionally, it is non-volatile, making it less prone to drift and drift-related damage. Wikipedia


330px MCPA structure

MCPA is a selective non-systemic broad-spectrum herbicide used to control weeds in both crops and non-crops. It is often used in combination with other herbicides to form weed management systems. MCPA selective weed killers are known for long-lasting control and excellent weed knockdown. It is also slower acting than many other herbicides, making it less likely to cause damage to crops. Additionally, it can be applied in colder temperatures, providing more options for its timing and flexibility in weed control. Wikipedia

Weedol is our recommended Fluroxypyr, Clopyralid & MCPA Weedkiller.


330px Mecoprop.svg

Mecoprop is a selective weedkiller, meaning that it targets certain types of weeds without harming the surrounding plants. It is effective at killing a wide variety of broadleaf weeds while leaving grasses, including lawn grass, unharmed. It is also safe to use around children and pets, and it breaks down quickly, so it does not linger in the environment. Wikipedia

Iron sulphate

330px Fe%28H2O%296SO4

Iron sulphate is a non-selective herbicide that is effective at killing weeds. It is particularly effective at controlling moss, algae and lichen and is safe to use around plants, pets and children. Iron sulphate is also a natural product, so it is safer for the environment than synthetic herbicides. Wikipedia

Scotts Miracle-Gro is our recommended MCPA, Mecoprop & Iron Sulphate Weedkiller.


330px Triclopyr

Triclopyr is a good choice to kill tree stumps. It is a systemic herbicide that can be applied as a basal bark treatment, cut-stump treatment, or basal-spray treatment. When it is applied as a cut-stump treatment, it is absorbed by the exposed wood and translocated to the roots, where it kills them.

Triclopyr is a weed killer that kills woody weeds and broadleaf weeds, such as thistles, dandelions, and clover. It is a select systemic weed killer, meaning it will move through the plant after application but is unlikely to be absorbed by nearby plants. Additionally, it is non-volatile, meaning it is unlikely to drift to nearby plants. Triclopyr is often used in combination with other herbicides for more effective weed control. The active ingredient in most Triclopyr products is ester-based and has low toxicity to wildlife and pets. Wikipedia

ORTHO is our recommended Triclopyr Weedkiller.


225px Dicamba.svg

Dicamba is primarily used to control weeds in turf grass. It is a broad-spectrum, non selective weed killer that can be used to control a wide variety of weeds. Dicamba is known for its fast-acting weed knockdown and excellent control of large-seeded broadleaf weeds, such as thistles, dandelions, and clover. It is often used in combination with other herbicides to provide more effective control of perennial weeds. Additionally, it has low water solubility and low volatility, making it more environmentally friendly than many other herbicides. Wikipedia


315px 2%2C4

2,4-Dichlorophenoxyacetic acid is a herbicide used to control broadleaf weeds and sedges. It is a systemic, broad-spectrum, non-selective herbicide that can be used on both cropland and non-cropland areas. It is known for its rapid weed knockdown and long-lasting control of broadleaf weeds and sedges. 2,4-D is also effective in controlling many persistent weeds, such as Canada thistle and oxalis species. Additionally, it has low temperature and pH stability, making it an ideal choice for controlling weeds in various climates and soils. Wikipedia


1200px Pyraflufen ethyl.svg

Pyraflufen-ethyl is a selective, systemic herbicide used for preemergent weed control in certain labeled crops. It works by preventing weeds from emerging from the soil and can provide season-long control of certain weeds. Pyraflufen-ethyl is generally safe to use on food crops, as it has low toxicity and low water solubility. It is also less prone to drift and drift-related damage, and does not persist in soil after application. Additionally, it is rainfast and can provide season-long control when used correctly. Further Information


The quest for a pristine garden often leads us to tools and formulas promising magic. However, understanding the science and intention behind these tools, especially weed killers, is vital. Armed with knowledge, you’re not just applying a product, you’re orchestrating a calculated dance between nature and nurture. The weed killer active ingredients are the unsung heroes, doing the heavy lifting while letting your garden’s stars shine bright. So next time you’re out in your patch of green, remember that it’s more than just weeding, it’s curating beauty, one ingredient at a time. Here’s to gardens that tell tales of care, precision, and informed choices.


Jonathan Gaze

Content Editor

Hello there! I’m Jonathan Gaze, Content Editor for Harry Rufus.

With my technical problem-solving skills and meticulous attention to detail, I present sustainable living advice clearly and understandably. I’ve developed a knack for filtering out the fluff, presenting you with only the most practical and reliable sustainable living guidelines.

Here’s what you can anticipate from my content:

  • Clear, reliable advice on sustainable living.
  • Informative articles that simplify complex concepts.
  • Trustworthy recommendations for eco-friendly practices.

I’m committed to making your transition to an eco-conscious lifestyle a breeze, turning challenges into opportunities.

Similar Posts