Ammonium Sulfate 21-0-0 Fertilizer
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Product Description
Fast-release nitrogen for quick green-up and improved lawn color. 21-0-0 Ammonium Sulfate provides 21% nitrogen and 24% sulfur to support active growth, improve turf color, and supply sulfur to lawns growing in high-pH soil.
Choose the granular formula for traditional spreader applications or the sprayable formula for light, controlled liquid feedings.
Why Choose 21-0-0 Ammonium Sulfate?
- Fast Green-Up: Provides readily available nitrogen for a quick turf response.
- Added Sulfur: Supplies 24% sulfur to support plant health and nutrient availability.
- Useful for High-pH Soil: Continued use can have an acidifying effect on alkaline soil.
- Supports Better Color: Helps improve pale turf caused by low nitrogen or limited nutrient availability.
- Two Application Options: Available in granular and sprayable formulas.
Best Uses
- Lawns that need a quick nitrogen boost
- Correcting visible nitrogen deficiency
- Improving lawn color during active growth
- High-pH or alkaline soil
- Granular or liquid spoon-feeding programs
Granular Application Rate
Apply 4–5 lbs per 1,000 sq ft.
- 18 lb bag: Covers approximately 3,600–4,500 sq ft
- 50 lb bag: Covers approximately 10,000–12,500 sq ft
Spread evenly over dry grass and water thoroughly after application. Avoid applying to dormant, drought-stressed, or severely heat-stressed turf.
Sprayable Application
The sprayable formula can be dissolved in water for lighter, more controlled nitrogen applications. Measure the product based on the amount of nitrogen you want to apply, then dissolve it completely in enough water to evenly cover the lawn.
- 0.25 lb of nitrogen: Use approximately 1.2 lbs of product per 1,000 sq ft
- 0.50 lb of nitrogen: Use approximately 2.4 lbs of product per 1,000 sq ft
Add the measured product slowly to the spray tank while circulating or agitating the water. Continue mixing until fully dissolved, then spray evenly over the lawn. Use sufficient water (recommend 2 gallons per 1,000 sq ft) for uniform coverage and rinse the spray equipment thoroughly after use.
Use with care: Ammonium sulfate is a fast-release fertilizer and may burn the lawn if applied too heavily, unevenly, or during stressful weather. Measure carefully and avoid overlapping applications.
Looking for longer-lasting feeding? Consider a controlled-release fertilizer such as Lawn Synergy Almighty 20-0-10.
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Details & Specifications
| Active Ingredient | Ammoniacal Nitrogen (N) 21% Sulfur (S) 24% Derived from Ammonium Sulfate |
|---|---|
| Lawn Types | Tall fescue, Bermuda, Zoysia, St. augustine, Centipede, Kentucky bluegrass, Ryegrass |
| Special Features | Granular |
| Application Rate | |
| Time to Apply | Spring, Summer, Fall, Winter |
| Delivery System | Dispersible Granules |
| For Use In | Turf Grass, Landscape Beds, Vegetable Gardens |
| Brand | Lawn Synergy |
Spreader Settings
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Customer Reviews
Overall rating: 4.75 / 5 from 20 reviews.
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Reviews
I use Lawn Synergy AS
"I use Lawn Synergy AS for smaller spoon feeding between my scheduled 20-0-10 applications every 6 weeks. Definitely helps keep that deep green color, but get ready to mow more frequently."
My line is better than
"My line is better than expected wonderful product. I even told my neighbors and some of my family. You got a good thing thank you."
Really great product and my
"Really great product and my lawn geern"
"I know this product!! Gurantee green grass. . . just follow instructions"
Haven’t retested soil
"Haven’t retested soil"
Didnt do anything for
"Didn't do anything for my lawn, (Bermuda). Nothing, didnt make it greener or give it growth. No more than any other fertilizer I've used. I'm totally dissatisfied with this one. Maybe one of your other product will work, but I will never know."
So Far So Good
"I believe using a Scott Spreader that I place too much at a setting of 5. Please tell me what setting I should use. So far so good."
Sulfate of Ammonia
"Good Quality prodct."
Fast shipping, low prices, high quality!
"Ordered some high sulfur based lawn fertilizer and the price was excellent. Shipping was fast and free and the product was high quality and easy to work with. I plan on ordering again from Lawn Synergy!"
Fast shipping, low prices, high quality!
"Ordered some high sulfur based lawn fertilizer and the price was excellent. Shipping was fast and free and the product was high quality and easy to work with. I plan on ordering again from Lawn Synergy!"
Q&A
- How much liquid per 1,000 sq foot ? I will be using my ego sprayer.
- It will depend on the spray rate. How many gallons per 1,000 sqft is your spray rate?
- I purchased from you 2 18lb bags of the above sprayable fertilizer. I have approx 14,500 square feet. I want to apply with my 20 gallon pull behind sprayer. How much fertilizer do I use per 20 gallons of water.
- Can you reach out to us directly at support@lawnsynergy.com We need more information to be able to assist you.
- Can I use 20-0-0 on my lawn in this time of year live in North Carolina when it is hot
- If you do, use the half rate, you're in the transition zone as I am as well. We've had plenty of rain to sustain a a lush lawn and though it's been hot the rain contributes to less drought and stress
- Can I use 20-0-0 on my lawn in this time of year live in North Carolina when it is hot
- My answer is yes l. I would apply in the coolest part of the day and then water it in, just before a rainstorm worked well fior me
- Can I use 20-0-0 on my lawn in this time of year live in North Carolina when it is hot
- No, this could cause burning due to high heat and higher nitrogen content. I would recommend using Emerald 10-0-20 instead for this time of the year.