Q4 Plus Weed Control
Q4 Plus Turf Herbicide for Grassy & Broadleaf Weeds Quart
Q4 Plus Weed Control
Q4 Plus Weed Control
Q4 Plus Weed Control
Q4 Plus Weed Control
Q4 Plus Weed Control
Q4 Plus Weed Control
Q4 Plus Turf Herbicide for Grassy & Broadleaf Weeds Gallon
Q4 Plus Weed Control
Q4 Plus Turf Herbicide for Grassy & Broadleaf Weeds Quart
Q4 Plus Weed Control
Q4 Plus Weed Control
Q4 Plus Weed Control
Q4 Plus Weed Control
Q4 Plus Weed Control
Q4 Plus Weed Control
Q4 Plus Turf Herbicide for Grassy & Broadleaf Weeds Gallon
Fast Shipping
Satisfaction Guaranteed
Made in the USA
Expert Support Available

Q4 Plus Weed Control

All-in-one weed killer for crabgrass, yellow nutsedge, and broadleaf weeds in lawns.
  • Fast Results
  • Simplifies Weed Control
  • Controls grassy + broadleaf weeds
$59.99

Timing: Apply when weeds are actively growing. Spring, summer, and fall

Select Size:

Selling Fast
Amazon
American Express
Apple Pay
Diners Club
Discover
Google Pay
Mastercard
PayPal
Shop Pay
Visa
Fast Shipping
Satisfaction Guaranteed
Made in the USA
Expert Support Available

All-in-One Post-Emergent Weed Control for Lawns

Four active ingredients. One complete weed control solution.

Q4® Plus Turf Herbicide is a professional-grade, post-emergent herbicide designed to control grassy weeds, sedges, and broadleaf weeds in a single application. With four powerful active ingredients working together, Q4 Plus eliminates the need for multiple products, making lawn weed control simple and highly effective.

It controls tough weeds like crabgrass and yellow nutsedge while also targeting common broadleaf weeds such as clover, chickweed, and dandelion. Enhanced with fertilizer components to support turf health, Q4 Plus helps your lawn recover quickly and grow thicker after weed removal.

What It Controls

  • Crabgrass
  • Yellow Nutsedge
  • Foxtail
  • Chickweed
  • Clover
  • Dandelion
  • And many other listed grassy and broadleaf weeds (see label for full list)

Why Choose Q4® Plus

  • Four-Active Formula: Controls grassy weeds, sedges, and broadleaf weeds in one product.
  • Crabgrass & Nutsedge Control: Eliminates two of the most difficult lawn weeds.
  • Broadleaf Power: Tackles clover, chickweed, dandelion, and more.
  • Fast Results: Visible weed decline in days.
  • Year-Round Flexibility: Can be applied whenever weeds are actively growing.

Lawn Types Safe for Use

  • Kentucky Bluegrass
  • Tall Fescue & Fine Fescues
  • Perennial Ryegrass
  • Annual Ryegrass
  • Bermudagrass
  • Zoysiagrass

Always verify turf tolerance and local restrictions on the product label before application.

Application Guidelines

  • Apply to actively growing weeds.
  • Use a properly calibrated sprayer for uniform coverage.
  • Avoid mowing 1–2 days before and after application.
  • Do not apply to drought- or heat-stressed turf.
  • Follow labeled rates based on turf type and weed pressure.

Best For

  • Homeowners who want one product to control multiple weed types
  • Lawns with mixed weed infestations
  • Cool-season and warm-season turf
  • Professional turf maintenance programs

Q4® Plus simplifies lawn weed control by combining crabgrass, nutsedge, and broadleaf power into one efficient, professional-grade solution.

Key Value
Active Ingredient Quinclorac - 8.43% Sulfentrazone - 0.69% 2,4-D, dimethylamine salt - 11.81% Dicamba, dimethylamine salt - 1.49% OTHER INGREDIENTS - 77.58%
Lawn Types Tall fescue, Bermuda, Zoysia, Kentucky bluegrass, Ryegrass
Special Features Rain fast in 6 hours. Contains a surfactant.
Application Rate Cool Season Lawns (2.6 to 3.0 fl. oz./1000 sq. ft.) Bermuda and Zoysia Lawns (1.8 to 2.6 fl. oz./1000 sq. ft.)
Time to Apply Spring, Summer, Fall
Shipping Restrictions AK, CA, LA, HI, MA, PR, NY, TX, WY, WV
Waiting Period to Seed Minimum 7 days, 14 days on Kentucky Blue Grass
Delivery System Liquid
Brand PBI Gordon
For Use In Turf Grass

Can I apply Q4 Plus weed control to my entire lawn?

Absolutely, you can blanket apply q4 plus on your entire lawn. However, we recommend taking advantage of our lawn care program which includes pre-emergents. Pre-emergents will greatly reduce weeds in the lawn making it much easier to spot spray weeds if needed.

Can I apply Q4 Plus using a hose on sprayer

It is not recommended on the label and it is more accurate to apply using a pump sprayer

How many sq. ft. will Q4 Plus cover?

1 qt. will cover 10,000 sq. ft. to 17,000 sq. ft.*
1 gal. will cover 42,000 sq. ft. to 71,000 sq. ft.*
*Depending on lawn type and oz./1000 mix rate. Always follow the label for application rates, mixing, and applying.

Free Shipping on Orders $39+

Choose Options

Overall rating: 4.2727275 / 5 from 22 reviews.

AI Generated Review Summary

Summary topics

Review topics: [].

Review highlights

Reviews

I applied as a direction

"I applied as a direction requested and also added sticker fluid but it barely killed the weeds I will try again or try different product"

Gene B. (1/5)

My first time using product,

"My first time using product, very impressed how weeds were dying without hurting grass. I would recommend Q4."

Thomas B. (5/5)

Doesn’t Work and Can’t Refund

"I rarely leave negative reviews, and I want to start by saying that I’ve had great experiences with Lawn Synergy overall. Their other products have worked well for me, and my past interactions with their team have been positive. That’s why this situation has been so frustrating. I purchased their Q4 herbicide for my tall fescue lawn here in Charlotte, NC to deal with the typical weeds we get in this region. After applying it exactly as directed, I saw essentially no effect on the weeds. I emailed Lawn Synergy about it, and they told me to wait two more weeks as apparently the product is extremely sensitive to temperature changes and because sometimes it takes longer to work. I did exactly that and waited. Two weeks later there was still no meaningful change at all. When I followed up again, asking for a refund since the product clearly wasn’t working, I was told they cannot refund opened products and that they are only the distributor, so I would need to contact a third party manufacturer to resolve the issue. From start to finish, this has been a frustrating experience: 1) Product didn’t work as advertised 2) I followed their instructions and waited longer 3) No resolution was offered Again, I really appreciate this company and what they have to offer, but this product is not up to their standard."

Bob (1/5)

Excellent

"Excellent, it works."

ADEYEMI O. (5/5)

Killed my tall fescue

"Killed my tall fescue"

Lisa P. (1/5)

Great product and price, but bottle leaking

"The product and price were great, but did not expect to have one of the bottles leaking upon opening the box. Bottles were shipped using paper bags as packing material."

Anonymous (3/5)

Q4 Plus Turf Herbicide for Grassy & Broadleaf Weeds

"Great results in a few days! Well satisfied with this product."

Randy B. (5/5)

No working yet

"I have applied it twice to my crabgrass in my Bermuda and so far it hasn’t worked. We did get rain after 12-14 hours so I will try again"

Wayne C. (3/5)

Great experience

"I did first just half of my property to see the difference, it did a great job, cleaned all weeds!"

Joel G. (5/5)

Shipping and delivery was

"Shipping and delivery was quick and fast. . . i havent used product yet but when i do i will be writing and taking pictures about it"

Sotiris (5/5)

Q&A

Is this correct, 16oz for 64oz of water in a tank sprayer for cool season lawns?
Depending on your lawn type, Mix 1.8-3 oz per 1 gallon. 1 gallon will need to cover 1,000 sq. ft. of the lawn area.
Can I apply four hours before rain?
Q4 requires 6 hours of dry time before it is rain fast
How long after before can pets be on it
As soon as it is dry, it's safe for people and pets.
How often should I use this product? I'm thinking of applying it to turf type tall fescue in mid July in Pennsylvania.
You can apply and spot spray as needed.
Will Q4 kill Creeping Charlie?
Yes! Creeping Charlie ground ivy is listed on the label.