Q4 Plus Weed Control
All-in-one weed killer for crabgrass, yellow nutsedge, and broadleaf weeds in lawns.
$56.95
$59.99
Product Description
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.
COMMON QUESTIONS
Frequently Asked Questions
Product resources
Product Information & Resources
Everything you need to understand, apply, and reference this product.
Details & Specifications
| 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 | |
| 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 |
| For Use In | Turf Grass |
| Brand | PBI Gordon |
Spreader Settings
Customer Reviews
Overall rating: 4.28 / 5 from 25 reviews.
AI Generated Review Summary
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Review highlights
Reviews
Awesome product. I can see
"Awesome product. I can see the crabgrass and weeds turning yellow and dieing to show off my beautiful lawn."
Product works amazing, the lawn
"Product works amazing, the lawn is weed free!"
Crabgrass control was ok, not
"Crabgrass control was ok, not great."
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"
My first time using product,
"My first time using product, very impressed how weeds were dying without hurting grass. I would recommend Q4."
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."
Excellent
"Excellent, it works."
Killed my tall fescue
"Killed my tall fescue"
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."
Q4 Plus Turf Herbicide for Grassy & Broadleaf Weeds
"Great results in a few days! Well satisfied with this product."
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.