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How to Use Barricade 4FL Pre-Emergent Herbicide

By DoMyOwn staff

Barricade 4FL Pre-Emergent Herbicide is a pre-emergent herbicide used for season-long control or suppression of listed annual grasses and broadleaf weeds.

 How to Use Barricade 4FL Pre-Emergent Herbicide Video Play

Video Transcript

Do you want to prevent weeds like crabgrass, goosegrass, spurge and more from growing in your lawn?  Look no further than Syngenta's Barricade 4FL Pre-Emergent Herbicide.

Barricade 4FL selective pre-emergent herbicide prevents the growth and development of over 30 grassy and broadleaf weeds in lawns and landscape ornamentals.  Containing the active ingredient Prodiamine, this weed preventer can be used on many warm-season and cool-season turfgrasses including bermudagrass, tall and fine fescues, St. Augustinegrass, Kentucky bluegrass, and more.

Barricade 4FL should be applied to your lawn prior to weed germination. It will not control weeds once they have already emerged.  Timing can vary by your location. As a general guideline, spring applications should be made after the last frost of the spring, but before the soil temperatures warm to 55 degrees Fahrenheit. Fall applications should be made once the soil temperatures begin to cool below 70 degrees, but before the ground freezes.

The application rate of this pre-emergent determines the length of residual weed control you will have.  Higher use rates will provide longer control and lower rates can be used in shorter growing seasons. 

The Application Timing and Rate Table on the product label can help you determine the length of residual weed control that you can expect after you apply the herbicide at different rates.  If you are applying Barricade 4FL in the spring to a cool season turf, and you plan to overseed in the fall, you may want a shorter length of control, thus a lower application rate, to ensure your grass seeds germinate in the fall.  If you are in an area where it warms up much earlier, and you will be applying the Barricade in early spring, you may look for a longer length of control and, therefore, a higher application rate. This rate table can help you understand the application rate and length of control provided.

Next, you will want to consult the product label to determine the Annual Use Rate for your turf type.  For example, in bermudagrass or centipedegrass, you can apply between 0.5 oz and 1.1 oz per 1,000 sq feet per year, while Kentucky bluegrass can be applied between 0.23 oz and 0.7 oz per 1,000 sq feet per year, and Fine fescue at 0.23 oz – 0.55 oz per 1,000 sq feet per year.  

Keep in mind the rates listed in this chart are the maximum annual rates.  If you plan to make multiple applications with Barricade 4FL throughout the year, you'll need to divide the maximum rate by the number of applications you plan to make to get your per application rate. For example, if you are treating Bermudagrass and plan to make 2 applications for the year, then you can use 0.5 oz per 1,000 sq ft per application without exceeding the maximum annual rate.

Barricade 4FL should be applied with a minimum of a half a gallon of water per 1,000 sq feet, but it is best to calibrate your sprayer beforehand to know how much water it takes for you to cover 1,000 square feet.  You can see our video on how to calibrate your sprayer to learn how to do this. Remember that the water is a carrier for the herbicide, so using the correct amount of Barricade 4FL (the active ingredient) is more important than using a specific amount of water.

Once you know how much Barricade 4FL and water you will need, you can make your spray mix.  Begin by filling your spray tank ¼ full of water. If you are using turf mark dyes, add those to your sprayer and agitate the mixture.  Then add the Barricade 4FL and agitate again.  While you are applying, continually agitate the tank to ensure a well-mixed spray suspension. 

Apply to your lawn, being sure to get even coverage.  For optimal weed control, you should activate this pre-emergent herbicide with half an inch of rainfall or irrigation before weeds germinate and within 14 days of application.

Refer the Barricade 4FL Pre-Emergent Herbicide product label for detailed application rates and usage instructions.

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