Weed Control FAQ's

• Can children and pets play on a lawn after a weed control product has been applied?
• When is the best time to control weeds?
• Are some lawn weeds more difficult to kill than others?
• I've used a lawn weed control product but it didn't work. Why?
• How does Lawn WeedOut® work?
• How long does Lawn WeedOut® take to work?
• How soon after applying WeedOut® can I mow my lawn?
• How soon after using Lawn WeedOut® can I water the lawn?
• How soon after treating my lawn with Lawn WeedOut® can I walk on it?
• Will Lawn WeedOut® leach in the soil and contaminate my well or nearby streams?
• What is the difference between Lawn WeedOut® and WipeOut®?
• How does WipeOut® Total Weed & Grass Killer work?
• How long does it take WipeOut® to kill weeds and grass?
• How do I get rid of Quackgrass in my lawn?
• How can I prevent crabgrass from growing in my lawn?
• Can I control crabgrass after it has germinated?
• Can I re-seed my lawn after using a weed control product?

Can children and pets play on a lawn after a weed control product has been applied?

Always allow the lawn to dry thoroughly before allowing children and pets to play on it. Do not allow children or pets near the lawn during application. Lawn WeedOut® will usually only take a few hours to dry. If you are unsure about drying time, as a safety precaution, observe a 24-hour period of no entry.

When is the best time to control weeds?

Most weed control products work best when weeds are actively growing. (For information on preventing crabgrass see Crabgrass Questions). Weeds, like most plants, grow best when temperatures are moderate, and moisture levels are adequate but not excessive. May, June, and September are the times of the year when these conditions are usually present. Early spring, mid summer, and late fall are times when it is often either too hot and dry, or too cold and wet for active plant growth, making herbicides less effective if used. When controlling weeds with Lawn WeedOut® or Total WipeOut®, daytime temperatures should be above 15° C and nighttime temperatures should be above 5° C. Do not apply during hot, dry conditions.

Are some lawn weeds more difficult to kill than others?

Some weeds are far more persistent then others and require additional effort to control. Also, some weeds have stronger natural defense mechanisms against weed control products. Creeping Charlie and Chickweed, for example, are hard to control weeds. Creeping Charlie has a small leaf comprised of thick cells. The stem of this weed sets roots at every point where it touches the soil, giving it a complex root system. These factors give it a natural defense system. These weeds will require 2 to 3 applications of Lawn WeedOut®. It is best to treat the entire lawn with Lawn WeedOut® first, and then spot treat only the resistant weeds like Creeping Charlie 7 to 10 days later. Make sure to apply when weeds are actively growing. Do not apply during hot, dry conditions.

I've used a lawn weed control product but it didn't work. Why?

Weed control products need certain conditions to be effective. Here are the main reasons why it may not have worked.

1. The most common reason weed control products aren't effective is that they are applied too early in the season. For best results weeds need to actively growing with temperatures consistently above 15° C during the day and above 5° C during the night.
2. Weeds with small leaves are difficult to control under the best conditions. This includes weed such as Clover, Creeping Charlie and Chickweed. These types of weed generally require 2 or 3 applications of a weed control product at about 7 to 10 day intervals.
3. During hot and dry conditions your lawn (including weeds) goes into dormancy. If the weeds aren't actively growing the weed control product will not be effective. Do not apply weed control products when the temperature is above 27° C.
4. There was poor contact with weeds. This can be caused by a couple of reasons;
   • Granular weed control product should be applied to a wet lawn to allow the particles to stick to the weeds.
   • Rain or watering within two days of application can wash the product off the leaves before it has time to work.
   • Mowing immediately before or after applying. Instead, mow your grass two days before applying a weed control product to stimulate growth of weeds. Do not mow again any sooner than two days after application.
5. The product directions were not followed. The coverage (and mixing rate for concentrates) has been carefully determined to deliver effective results. Read the entire label and follow all directions.
6. Lawn weed control products are used to control broadleaf weeds such as dandelion and plantain. Grassy weeds such as crabgrass will not be affected. To control crabgrass and other grassy weeds, use Crabgrass Preventer rather than weed and feed.
7. The weeds in your lawn are not listed on the label. Although Weed control products are effective on most broadleaf weeds, there are a few that are not affected.
8. Lawn weed control products work on direct contact only. They will not prevent new weeds from growing after a weed control application.

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How does Lawn WeedOut® work?

Lawn WeedOut® contains growth stimulants similar to plant hormones. This causes rapid cell division that destroys the cells and blocks water and nutrient transfer causing the weed to die. Weeds are best controlled when they are actively growing. This ensures that absorption of the product by the weed will be as thorough as possible.

How long does Lawn WeedOut® take to work?

Most broadleaf weeds will die within one week after applying Lawn WeedOut®. Some creeping weeds, such as Creeping Charlie and Chickweed may require 2 treatments, 2 to 3 weeks apart. Weather conditions often dictate how quickly Lawn WeedOut® will achieve control on lawn weeds. Excessive heat, dryness, or cold can put weed plants under stress, which reduces the effectiveness of the product. It is best to apply Lawn WeedOut® when growing conditions are good; temperatures should be over 15° C and under 27° C, and recent precipitation should be adequate but not excessive.

How soon after applying WeedOut® can I mow my lawn?

Your lawn should not be mowed for at least 3 to 4 days after applying liquid or granular weed control products. It is important to allow the weed control product time to fully absorb into the leaves of the weed. Mowing the lawn too early may cut off part of the weed before the product has absorbed and been distributed throughout the tissue of the weed.

How soon after using Lawn WeedOut® can I water the lawn?

You should wait at least 2 days before watering your lawn. Weed control products should be applied when 1 to 2 days of clear weather are forecasted. This ensures that absorption of the product by the weed will be as thorough as possible.

How soon after treating my lawn with Lawn WeedOut® can I walk on it?

Do not allow people (other than the person applying the product) or pets on treatment area during application. Do not re-enter the treated area until the spray has thoroughly dried. Lawn WeedOut® will usually only takes a few hours to dry. If you are unsure about drying time, as a safety precaution, observe a 24-hour period of no entry.

Will Lawn WeedOut® leach in the soil and contaminate my well or nearby streams?

When applied at the correct rate, Lawn WeedOut® should absorb entirely into the plant. After killing the weed, the product will break down into naturally occurring compounds. Lawn WeedOut® will be virtually undetectable after two weeks. Lawn WeedOut® has a high affinity for the organic matter in the soil, so it will not move from where it is applied. This prevents it from leaching into the ground water.

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What is the difference between Lawn WeedOut® and WipeOut®?

Lawn WeedOut® will control all major lawn weeds and will not harm the lawn. Lawn WeedOut® is a selective herbicide and is formulated to kill only a specific group of lawn weeds, including: Dandelions, Plantain, Chickweed, Knotweed, Black Medic, and Clover. WipeOut® is a total weed & grass killer that will kill all plants including the grass. WipeOut® is a non-selective herbicide, meaning that it will kill all of the vegetation that it comes into contact with. When using WipeOut® Total Weed & Grass Killer be careful to apply it only on the plants that you want to control.

How does WipeOut® Total Weed & Grass Killer work?

While growing, plants produce ammonium. WipeOut® Total Weed & Grass Killer inhibits the production of the enzyme responsible for changing the toxic ammonium into organic compounds, resulting in the accumulation of ammonia in the plant. This build up of ammonia causes many of the plants' systems to shut down including photosynthesis, killing the plant.

How long does it take WipeOut® to kill weeds and grass?

WipeOut® Total Weed & Grass Killer will start to work within 1 to 2 days, with total kill in 4 to 7 days. Within 48 hours of applying WipeOut® you will begin to see weed leaves changing colour and turning brown; total burn down will occur in 7 days. WipeOut® is one of the fastest working weed and grass killers available. Weather conditions play a part in how fast and effective WipeOut® will be. Cool temperatures and dry soil conditions place plants under stress, which reduces the speed of action for this product. Rainfall within 4 hours of applying the product may also reduce its effectiveness.

How do I get rid of Quackgrass in my lawn?

Quackgrass is a perennial weed that propagates by long roots called tillers. It has a long, tapered, blue green blade that wraps around the stem of the plant in a claw like formation. A persistent weed, it is virtually impossible to pull quackgrass out by hand. A selective herbicide such as Lawn WeedOut® will not control quackgrass. The only solution to controlling quackgrass is to apply a non-selective herbicide like Total WipeOut® to the lawn; this will kill both the lawn and the quackgrass. After this step, re-seed the lawn with premium lawn seed such as C-I-L® Golfgreen™. C-I-L® Golfgreen™ Lawn Starter fertilizer will help to quickly reestablish a healthy lawn. Quackgrass is a persistent weed that requires drastic measures to control. A second application of Total WipeOut® may be required for severe infestations of quackgrass.

How can I prevent crabgrass from growing in my lawn?

Crabgrass is an annual weed that grows from seed every year. Apply C-I-L® Golfgreen™ Lawn Fertilizer with Crabgrass Control in early spring. For best results it should be applied before crabgrass plants germinate, usually in the early spring when the forsythia bush is in full bloom.

Can I control crabgrass after it has germinated?

C-I-L® Golfgreen™ Lawn Fertilizer with Crabgrass Control can be used at higher rates to control crabgrass up to the three-leaf stage, usually mid-June.

Can I re-seed my lawn after using a weed control product?

Different herbicides will affect lawn seeds differently:

WipeOut® Total Weed & Grass Killer - Has no soil activity and will breakdown very quickly. There are no replanting restrictions.

Lawn WeedOut® - Has some soil activity and takes about two to three weeks to breakdown. Lawn seed should not be planted for 3-4 weeks after using Lawn WeedOut®. Lawn WeedOut® should not be applied to newly seeded lawns until after the third mowing.

C-I-L® Golfgreen™ Lawn Fertilizer with Crabgrass Control - Creates a herbicidal barrier on the surface of the soil, preventing the emergence of crabgrass seeds. However, this barrier will also prevent the germination of lawn seed. It is advisable to seed your lawn in the springtime, allowing the grass seed to germinate adequately, and then apply Crabgrass Preventer at the appropriate time. If, however, you have already applied Crabgrass Preventer, it is possible to seed your lawn in the fall. Fall is an excellent time to renew a lawn using a C-I-L® Golfgreen™ grass seed.

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