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Guardian Pre-emergent 13-0-10 Lawn Fertilizer with Prodiamine
Stop Crabgrass Before It Starts — Or Deal With Weeds All Summer
$39.99
Make It Easy – Auto Delivery Program
Product Information
Product Information
Guardian 13-0-10 is a professional-grade pre-emergent fertilizer designed to do two jobs at once — prevent crabgrass and annual weed seeds from germinating while feeding your lawn for deep green, steady growth.
If you want a clean lawn without fighting weeds all summer, this is where you start.
What Guardian Prevents
- Crabgrass
- Goosegrass
- Poa annua (annual bluegrass)
- Spurge
- Chickweed
- Oxalis
Guardian contains .37% Prodiamine, creating a long-lasting soil barrier that prevents weed seeds from germinating.
Why Guardian 13-0-10 Is Different
- Nitrogen for rich green color — promotes steady top growth without excessive surge.
- Slow-release nitrogen — feeds gradually for extended performance and improved efficiency.
- Potassium — strengthens roots and improves drought, heat, and disease tolerance.
- Professional-grade formulation — built for consistent, even results.
- Bio-based — enhance soil structure and naturally support long-term lawn health.
The result is a thicker, darker lawn that naturally crowds out weeds.
Ideal For
- Tall Fescue
- Kentucky Bluegrass
- Bermuda
- Zoysia
- St. Augustine
- Centipede
⚠️ Do not apply if you are planning on seeding. Prodiamine prevents all seeds from germinating, including grass seed for up to 3-4 months.
Product Details
Product Details
| Active Ingredient | .37% Prodiamine |
| Lawn Types | Tall fescue, Bermuda, Zoysia, St. augustine, Centipede, Kentucky bluegrass, Ryegrass |
| Special Features | Prevents weeds and slowly feeds lawn |
| Application Rate | |
| Time to Apply | Spring, Fall |
| Waiting Period to Seed | 120 Days |
| Delivery System | Granules |
| Brand | Lawn Synergy |
| For Use In | Turf Grass, Landscape Beds |
Documents & Labels
Documents & Labels
Got Questions?
Frequently Asked Questions
Overall rating: 4.604027 / 5 from 149 reviews.
AI Generated Review Summary
Guardian Pre-emergent 13-0-10 Fertilizer offers a balanced nutrient mix for lush, green lawns while effectively preventing weed germination. Its slow-release nitrogen ensures long-lasting green color and improved stress tolerance. Easy application and compatibility with various grass types make it a popular choice for maintaining a healthy, weed-free lawn.
Summary topics
- Lawn Appearance: 15%
- Grass Greening: 10%
- Customer Service: 15%
- Lawn Aesthetics: 8%
Review topics: [].
Review highlights
- "With the exception of removing about two dozen overall the lawn looks very well." —
- "Very easy and quick shipping and delivery." —
- "Grass is looking great!" —
Reviews
Very happy with my applications
"Very happy with my applications of 13-0-10. My lawn is pretty much weed free and super thick and green. I have received numerous compliments and questions as to what I'm doing to get my lawn looking so good. I was happy to pass on the name of your company and amazing products. Thank you!"
Using Lawn Synergy’s subscription service,
"Using Lawn Synergy’s subscription service, I have applied two applications of Guardian thus far and have had spectacular results! Golf course looking lawn with deep green color. I also used their spot weed product Q4 Plus Turf Herbicide periodically and the lawn is almost weed free! Watering regularly and mowing using the highest setting. Summers in NC are tough on tall fescue, so that will be the true test! Highly recommend!"
Great looking lawn
"I've cut my front lawn 4 times already and it's due for mowing again tomorrow. This is my second year on the program and I'm very happy with the results. I sent in a soil sample and the fertilizers Tony has recommended have given me a lawn with strong, green blades of grass. ."
Good stuff. I have to
"Good stuff. I have to leave a portion on my yard untreated because we have bees, so I use that as a control. But it also tends to spread out, so far the damage has been well managed because of this stuff. And my grass is noticeably darker and thicker. Second application is coming up pretty excited"
I tried this for the
"I tried this for the 1st time this year on my Bermuda grass in NC. It appears to have worked really good so far and majority of the weeds that I am used to seeing everyear have so far been at bay except a handful. I had also applied 0-0-7 a few weeks earlier than this so that could have further helped my lawn."
I am still waiting for
"I am still waiting for results. I have been applying the products since last year. I actually used pre-emergent but did noticed a lot of weeds since late winter early spring. I have been pulling weeds since I don't like using extra weed killers. I will see how this month ends l."
Too soon to tell, but hopeful
"While it's too soon tell to give full review, I will say the product went down without issue and did get some green up shortly thereafter; however, we did have a little weed breakthrough. I'm hoping as we get into peak summer season the crabgrass will be minimal, which is the main thing we are trying to stop. We also used the 0-0-7 early spring."
Hi Tony & Peter, I
"Hi Tony & Peter, I have been buying several products from LawnSynergy and was disappointed this time with the Guardian. I applied the pre-emergent the last week of March based on the thawing calendar as it said the best time to apply was before it hit 55 degrees consecutively and so I timed it accordingly. I live in the Northern suburb of Chicago. Two weeks post application, I saw significant increase in the weeds especially dandelions, clover and bull thistle. While the pre-emergent significantly addressed the poa annua which I had a problem last year and did not see at all this year, however I was surprised to see an uptick in other weeds, especially clover and dandelions. Thanks, Umesh"
Grass greened very nice ,
"Grass greened very nice , however I’m still have weeds growing. Not terribly disappointed cause it does look better."
My opinion is still out.
"My opinion is still out. I started using Lawn Synergy last year and bought the subcription this year. Last year I power raked the entire yard applied your seed and suggested fertilizer. This year it looks like it was never powerraked when each time time for the rest of the season it was bagged. Applied the Gauardian when recieving it hoping it woudl thicken the lawn why preventing weeds. Which it has not done either. So still holding out hope."
Q&A
- How soon will I observe the weeds dying, and when can I expect the grass to regain its vibrant green color?
- I applied13-0-10 pre-emergent in mid February to hopefully stop weeds from coming up. The second application in mid-April will hopefully **** the weeds that managed to escape the first application.
- Hi, does 13-0-10 Guardian Pre-emergent Fertilizer need to immediately be watered in, what's recommended?
- It is best to go ahead and water it in, and make sure that you avoid laying it down right before a heavy rain.
- Hi, does 13-0-10 Guardian Pre-emergent Fertilizer need to immediately be watered in, what's recommended?
- Yes
- Hi, does 13-0-10 Guardian Pre-emergent Fertilizer need to immediately be watered in, what’s recommended?
- Yes, I did water it in, but I don’t think it was necessary. There was heavy dew in the morning after I applied it, and it dissolved within a few days.
- Is this safe for animals after use of this product?
- I don't have any animals therefore I don't know if this product is safe for animals.