How long does it take weed b gon to work?

UC home and landscape guidelines for Weed Management in Lawns. Perennial weeds survive for many years, and though they produce seeds, many primarily weed problems, continue to work the soil without irrigating for several months to bring up new propagules. .. Ortho Weed B Gon Weed Killer products, yes. Use the companies in the quick links at the top of the page to Doesn’t have a long lasting effect. . I use Prodiamine and this takes care of most of the problems. If shade is from a house, remove the house for a beautiful lawn or . names, for example Weed B Gon CCO (Triclopyr) or Ortho Killex (2, 4-D. Ground ivy does well in sun or shade as long as soil is damp. Treat the lawn with Orthoe Weed-B-Gone Weed Killer for Lawns or Scottse is in spring, when shoots are just appearing; use Orthog Grass-B-Gone Grass Killer for It often takes hold in a lawn in areas of heavy traffic, then invades the surrounding area.

However, when they start taking over your lawn and every sidewalk crack, it may be time to break out the herbicide. Ortho Weed-B-Gon will kill. Depending on which one you use, results may be visible in only a couple of hours to gardeners everywhere, and the sooner they’re gone, the better. If weeds are taking over your lawn, Roundup makes a product . Kill Dandelions Without Chemicals · How Long Does Ortho Weed-B-Gon Take to Work?. Ortho Weed B Gon Weed Killer For Lawns Ready-To-Spray 2. Home / Selective Post Emergent Herbicides It is formulated with special ingredients to effectively kill over weeds such as For use in: Ryegrass, Kentucky bluegrass,Tall and Fine fescues, Bermudagrass, . DIY and Treatment Guides.

It can bring out the best in your home, so it’s a must to look for the most effective weed killer that will guide you in ensuring that it continues to bring out its .. It performs well while ensuring that its effects stay for a long time. .. clover, and oxalis infestation then you may want to use Ortho Weed B Gon to finally get rid of them. It’s far from perfect, but a “got what you paid for” result. I bought the LARGE jug of weed b gone, and started spraying. DECORATING GUIDESColor Guide: How to Work With Black. By Samantha Schoech. Take a walk on the dark side — your home has nothing to fear with this color when you know. The Best Weed Killers in for Maintaining Lawns Reviewed Which are the best strategies for taking care of such plants? Even during rainy months, therefore, you can use it worry-free at home or your office. Takes a long time . Look for Ortho Weed B Gon to get an effective weed killer that is.

You can use a pump sprayer to spray vinegar The National Coalition for with man-made hallucinatory How long does it take for Ortho Weed-B-Gone to be . Can I over-plant grass seed a day after spraying Ortho Weed B Gon? .. Home Guides Effects of LV 2, 4-D Weed Killer on Horses; Will Atrazine Kill My Flowers?. Ortho Weed B Gon plus Crabgrass Control Ready-To-Spray2 is guaranteed to kill crabgrass, dandelions and other listed common lawn weeds to the root!. Ortho Weed B Gon Weed Killer for Lawns Ready-to-Use Trigger is guaranteed to kill weeds to the root but not your lawn. Kill over types weeds without.


Dandelions are starting to show their bright, yellow faces this spring and like it or not, they’re going to make their annual appearance in our lawns. Whether you can tolerate their short-lived bloom or endure watching their wispy seed pods spread their seeds into the wind — from your neighbours lawn onto yours — we Ontarians have little treatment options available to us for any sort of weed control in our own back and front yards.

With the introduction of the Ontario Pesticide ban in 2009, our government has left us with limited options for killing the dreaded dandelions and invasive weeds in our turf. There are non-selective (kills everything) products on the market that work well on decks, patios, walkways, etc., in the place of ‘Round-Up’ and ‘WipeOut‘ products that have been banned for domestic use.

These non-selective weed control products pictured above are formulated with acetic acid (vinegar), sodium chloride (salt) or fatty acids. They will do a decent job of killing weeds but they cannot be applied directly on your lawns as grasses will be killed as well as the weeds. These products have a fast burn-down effect and tend to be rather distastefully aromatic.

There is really only one other available option that consumers can buy to kill weeds in the lawn that is available in Ontario. Well-know manufacturer, Scotts, is marketing an iron-based weed control product called ‘EcoSense‘ Weed-B-Gon.

Wright’s Feeds ‘N Needs stocks this Scotts product, which is an effective weed killer spray that kills weeds — not lawns.

It controls and suppresses a wide range of weeds including Dandelion, English Daisy, False Dandelion, White Clover, Black Medic, Bull Thistle, Canada Thistle, Common Chickweed, Creeping Buttercup, Slender Speedwell, Narrow-leaved and Broad-leaved Plantain, Dove’s-Foot Geranium, Lawn Burweed, Moss and Algae.

This product is available in varying sizes of the ‘Ready-To-Use’ formula as well as in a concentrate to mix with water in your own sprayer.

When applied, this iron-based weed control product absorbs through the leaves and roots causing the leaves to essentially ‘rust’, through iron oxidation, at the cellular level. This causes the weed to dry up, turn black, shrivel and die. The results of this treatment are visible within hours of application.

The only negative effect is the slight darkening of the surrounding grass area where treatment was applied. The darkened lawn will return to normal green colour within days, when used as directed and these results are dependent on the weather conditions as well.


— Apply Weed-B-Gon to individual weeds in your lawn and preferably not as a blanket-coverage spray to reduce the extent of the darkening damage to the grasses.

— Use on well-established grass lawns consisting of one or more of Kentucky bluegrass, perennial ryegrass and fescue.

— Do not apply to drought-stressed grass or when daytime temperatures exceed 30C.

— Do not apply to bentgrass or to newly-seeded areas or seeded lawns less than one year old.

— Do not apply if rain is expected within three hours.


First of all, if you have more than a few feet of clover or a high concentration of weeds to kill, you’ll find it much easier to use an herbicide sprayer. They are available in 1-gallon, 2-gallon and 3-gallon sizes here at Wright’s Feeds ‘N Needs. A sprayer with a wand is preferable, not one where the spray head is attached to the container. Secondly, you’ll get better results if you thoroughly water the area to be treated before you do any spraying. Dry leaves don’t absorb liquids as well, so wet the area you plan to treat and then allow it to dry up a bit so there is no pooled water on the leaves.

The next tip is to use an insecticidal soap to also spray down the areas to be treated, especially if you are targeting clover or other waxy-leaved weeds. If no soap is used, the product tends to bead up and run off the leaves resulting in unsuccessful coverage and thus a non-effective kill. The soap acts as a surfactant which reduces the surface tension on the weeds to allow the herbicide to stick better to the leaves. The product will remain on the weeds longer for a better knockdown result and the soap will not harm the grass. Again, wait for the soap to soak into the leaves and/or disperse before continuing — things should be moist but not wet when you continue. Usually the time it takes to empty and rinse your sprayer and load up the Weed-B-Gon is enough.

Lastly, load up your Weed-B-Gon solution into your sprayer. If you’re using a Ready-To-Use (RTU) formula, make sure to dump the entire contents into the sprayer so you can shake it up before and during application. If you’re using the concentrate formula (mixing it at the ratio of one part concentrate to 24 parts water) make sure, again, that you shake the mixture very well in the sprayer before and during application.

When treating your lawn, make certain to soak the weeds thoroughly and don’t be stingy with your application. If money is an issue, it might be more cost-effective to dig the weeds out by hand. Otherwise, if you’ve spent the money and are investing your time, you may as well follow the directions correctly to get the best results. Sometimes, with a heavy or concentrated infestation of weeds, a second application may be necessary in a few weeks time.


Overall, the feedback we’ve heard for this product is very favourable. However, the Ready-To-Use bottle sprayers are not the most ideal method to deliver the product onto the weeds but they are the most cost-effective for spot treating small areas. It’s not the manufacturer’s fault as they want to provide a cheap option for homeowners with smaller properties. Some consumers have found that coverage was much more even, complete and much easier with a proper pump sprayer using a wand, especially when treating large, country properties — not to mention after you pump it up you aren’t squeezing a trigger a thousand times or constantly bending down to get each little weed.

Consider giving Scotts ‘EcoSense’ Weed-B-Gon a try on the weeds in your lawn this year and if you have any questions or if you’re looking for information on calculating coverage, please contact Melanie at [email protected] .

Latest News from Control Solutions, Inc.

The Difference Between Eraser and Eraser Max

Eraser Herbicide contains the active ingredient glyphosate. It is a non-selective, broad-spectrum product – it will kill virtually any growing plant that you spray it on. (See the product label for a list of all plants controlled.) When Eraser is applied to actively growing plants, it’s taken up by the foliage and moves to the roots and growing points, stopping growth and killing the plant. Eraser works slowly; it can take up to 2 weeks for plants to be completely killed.

Eraser Herbicide has no activity in soil; it must be applied to the foliage of actively growing plants to be effective. The lack of soil activity also means that Eraser has no residual activity, and it will not affect nearby untreated plants. Treated areas may be replanted 1 – 3 days after application of Eraser (see label for details).

Eraser Herbicide

Eraser Max Herbicide contains glyphosate, as well as another active ingredient, imazapyr. This makes Eraser Max a very different product in several important ways:

  • Imazapyr is active in soil where it is taken up by plant roots.
  • It can move through the soil into parts of the landscape where it wasn’t sprayed, damaging plants there.
  • It is a long-lasting product, with residual activity lasting up to one year.

Eraser Max Herbicide

Because of this, there are some important precautions to follow when applying Eraser Max:

  • Only apply to areas where no vegetation is desired for one year.
  • Do not apply over the roots systems or desirable plants. For trees and shrubs do not apply closer than twice the distance from the trunk to the drip line as roots may be within this area.
  • Do not apply to slopes in landscape as movement on soil surfaces may damage desirable plants down slope.
  • Do not apply next to a fence if desirable vegetation is growing on the other side, or if future planting is intended.
  • Do not use before planting lawns, fruits, vegetables, flowers, or other plants because this product remains active in soil for up to one year.

Eraser Max is ideal for fence rows, gravel paths, sidewalks, driveways, parking areas and around farm buildings and barns – places you don’t want anything to grow. One application kills weeds for up to one year.

Thread: How Long to Plant After Spraying Roundup??

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How many days is glyphosate still active in the soil?

Expert response from Andrew Kniss

Associate Professor of Weed Ecology & Management, Department of Plant Sciences at the University of Wyoming

Wednesday, 02/10/2013 14:42

The soil half-life of glyphosate is approximately 47 days (with a range of 2 to nearly 200 days depending on soil type and various environmental conditions). But it is not active for a vast majority of that time. In order for glyphosate to be active as a herbicide, it must first (obviously) enter the plant. But glyphosate binds very tightly to soil particles almost immediately upon reaching the soil, and pesticides are not absorbed by plants while they are bound to the soil. Glyphosate is degraded relatively quickly by soil microorganisms, so there is almost never enough available glyphosate in the soil to cause plant injury. So although glyphosate can be detected in the soil for quite some time after application, it has no practical soil activity as a herbicide. We can spray glyphosate to control emerged weeds and plant a new crop on the very same day in most cases without risk of injuring the crop.

To be effective, how long does Glyphosate weed killer need to be applied before it rains?


“Foliar absorption of herbicides occurs in a liquid phase only; once a water droplet has dried on the leaf surface and herbicides have crystallized little to no additional absorption occurs. Therefore, any environmental condition speeding the drying of spray droplets on a leaf surface will reduce absorption. Low humidity and high winds can greatly reduce drying time, thereby allowing little time for absorption to occur. Conversely, high humidity with little wind slows the rate of drying and lengthens absorption time. Rainfall shortly after (< ½ hour) glyphosate application can wash spray droplets from the leaf surface. A foliar application should be “rain fast” once droplets have dried on the leaf surface.

Temperature, soil moisture, and solar radiation that optimize plant growth facilitate absorption and translocation of glyphosate. When photosynthetic rates are high photoassimilate produced in leaf epidermal cells is rapidly loaded into the phloem, other organic molecules like glyphosate are similarly loaded, and both are quickly translocated to sink organs. The rapid removal of glyphosate molecules from epidermal cells maintains a high concentration gradient that increases absorption rate. The time of day glyphosate is applied can also impact its efficacy. Applications made between 9 a.m. and 6 p.m. tend to maximize glyphosate activity. Short-lived temperature spikes (> 90 ºF) can also enhance absorption by reducing cuticle viscosity and allowing easier passage of foliar-applied herbicides.”

From Purdue University:

“Glyphosate must penetrate the leaf surface to provide effective weed control. While absorption occurs relatively quickly, rain after an application can wash glyphosate off before it has a chance to enter the leaf. The rain-free period required to prevent reduced activity is in uenced by the susceptibility of the target weed and the glyphosate rate. Small weeds of a sensitive species will require a shorter rain-free period than large or dif cult to control weeds. A 30-minute rain-free period may be adequate under ideal conditions. When spraying larger weeds, however, several hours between application and rain may be required to avoid reduced activity. Differences in rainfastness among glyphosate products are generally small. Adding more surfactant appears to have marginal benefits on the rain-free requirement.”

Now that spring has sprung, television, newspaper and magazine ads are sprouting with all sorts of plugs for weed killers. If you have never curled up on the couch with a dry book on botany, you might wonder how they work. How does a weed killer sprinkled on the lawn kill the weeds but not the lawn? Do herbicides recognize the difference between good plants and bad?

Interesting stuff, these weed-killing chemicals, for they are not as urbane and refined as you might think.

The way they work is to interfere with growth, either by blocking photosynthesis and protein production, or destroying or inhibiting root formation.

Herbicides disrupt plant growth, so they are not considered as dangerous to people as pesticides are, says Jeff Gillman, associate professor in the department of horticultural science at the University of Minnesota and author of “The Truth About Garden Remedies” (Timber Press). The thinking behind this theory is that the human body has little in common with plants, unlike the parts of our physiology that we share with bugs such as bloodstreams, brains and nervous systems.

Still, you should use chemicals in your yard with caution. There is a lot about herbicides and how they work that science doesn’t understand.

• Put pets indoors.

• Always wear long sleeves, gloves and goggles, and pull out the pith helmet.

• Read the label to find out how long you must stay out of the treated area.

Used correctly, herbicides will kill plants – some you didn’t intend to kill.

But they are not so hot for the environment. Some break down in the soil in just a few days, while others linger for many months or even years. They may leach into the root systems of nearby plants, and trickle down to the water table. Don’t forget that all water finds its way to the ocean, and there are plants out there in the deep blue sea.

Herbicides aren’t the only weapon to fight weeds. Mulch your garden beds to smother weeds and promote a healthy lawn so interlopers won’t have a chance.

“I have access to many chemicals but choose to use a hoe myself,” said Chris Roy, manager of Orange County Farm Supply in Orange.

Even so, as a last resort there is always that time or two in your gardening career when you get overrun with oxalis or dandelion and you will want to resort to chemicals. As you stroll the herbicide isle, remember that not all weed killers are created equal. Here are a few label descriptives you should know:


Post-emergent– These chemicals are applied to leafy areas of plants that are green and actively growing.

Pre-emergent– These chemicals are applied to soil areas before plants emerge. The weed is either winter or summer dormant with no top growth at the time, or still in the seed stage.

Monocot– Think strappy leaves. “Monocot” describes single-cotyledon plants such as lawn grass, weed grass, ornamental grass, corn, cereal grains, bamboo, iris, lilies and orchids. This is an important term to know if you are shopping for selective types of herbicide.

Cotyledon– Cotyledons are those weird first “leaves” that pop above the ground when a seed germinates. Cotyledons are not true leaves, but food storage systems that help the plant out until the true leaves appear. There are two cotyledons for dicot plants, and one cotyledon for monocot plants.

Dicot– Double cotyledon plants include everything on the planet except the few listed above. You will find selective herbicides designed just for dicots.

Selective herbicides– They’re designed to kill dicots or monocots, but not both.

Nonselective herbicides– They’re designed to kill all plants.

Total vegetation herbicides– They not only kill all plants but prevent them from growing in a given area for up to a year.


“Always use chemicals in the morning because the stomata (plants cells) close up when the temperatures reach around 80 degrees,” Roy said. “Later in the day the plant won’t absorb the chemicals.”


Glyphosphate is a postemergent herbicide that works like an antibiotic. Antibiotics destroy enzymes in certain bacteria that make you ill. Once the enzyme is destroyed, the whole germ cell dies.

Glyphosphate, usually sold as Roundup, works the same way by destroying a critical plant enzyme, EPSP synthase. Once the enzyme is destroyed, protein production stops and plant cells die.

This herbicide works best on warm days during the active growing season. It also works best with an ounce or two of liquid fertilizer in the mix.

Because it’s nonselective, it kills all plants it comes in contact with. On a windy day, drifting spray can unintentionally kill plants nearby. Roses are especially vulnerable.


Corn gluten is an example of a pre-emergent herbicide. It contains a naturally occurring chemical that corn produces to prevent other species from growing nearby, thereby eliminating competition.

This natural plant preventive works on lawn weeds by providing a barrier on the soil surface that discourages weed seeds from germinating. It works best on leafy dicots such as oxalis and dandelion. If used in the correct dosage, it will not harm monocots such as lawn grass.

The chemical barrier is critical. If you destroy the barrier by digging a hole, let’s say, weeds will pop through in that area.


Broadleaf weed killers are selective herbicides that work in lawns by targeting dicots that are actively growing while not harming the monocots such as lawn grass. The most common type of broadleaf weed killer is 2,4-D also known as Trimec.

2,4-D is an auxin or plant hormone that, when applied to the leaf area, simply confuses the plant to death. Since auxin is the hormone that makes plants grow, when it’s sprayed over the entire plant, the plant doesn’t know which way to grow, becomes deformed, then dies.


Fluazifop is the active ingredient in grass killers, working in exactly the opposite way as broadleaf weed killers by targeting the monocots. Fluazifop kills weed grasses such as Bermuda, kikuyu and others in flower beds and ground covers.


Heavy-duty soil sterilizers or total vegetation killers, such as Triox, are not available to the public anymore, but many of you likely have them in your storage sheds. These contain very strong chemicals that linger in the soil for years, and can kill plants growing nearby or downhill from where it is used even months after the application.

Contact the writer: (714) 796-5023 or [email protected]

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