Ammonium Sulfate Fertilizer 21-0-0
Best nitrogen booster for gardeners needing to acidify alkaline soil.
Elevate your garden's health with Greenway Biotech's Ammonium Sulfate Fertilizer. This 21-0-0 formula delivers fast-acting nitrogen for rapid greening and vigorous growth, complemented by 24% essential sulfur to boost chlorophyll and aid in soil acidification. Its 100% water-soluble nature ensures quick nutrient absorption for immediate results. Ideal for lawns, vegetables, fruits, and acid-loving plants, this USA-made fertilizer is CDFA registered and third-party tested for purity and effectiveness. It's a reliable choice for achieving vibrant, healthy plants and correcting alkaline soil conditions.
$24.99
Owner Satisfaction
4.7
/ 5
Category Rank
50
/ 4425
#50 in Fertilizers
Price vs Category Average
-59%
Below average
NPK Ratio
2100
/ --
Who it's for
- Gardeners seeking immediate visual results and lush foliage
- Growers cultivating acid-loving plants in alkaline soil conditions
- Plant enthusiasts prioritizing long-term health and enzyme development
Who should skip it
- Gardeners looking for an all-in-one complete nutrient solution
- Novice gardeners prone to over-application or uneven distribution
- Homeowners maintaining turfgrass that requires neutral soil pH
Performance breakdown
Nutrient Solubility
Fully water-soluble formula ensures rapid uptake for immediate plant response.
Soil Acidification
High sulfur content effectively lowers pH for acid-loving plant varieties.
Nitrogen Potency
Concentrated ammoniacal nitrogen drives aggressive greening and vigorous vegetative growth.
Purity Standards
Rigorous third-party testing guarantees minimal heavy metals for safer gardening.
Application Versatility
Adapts easily to foliar sprays or soil drenches for flexible feeding.
Quality Assurance
CDFA registration provides professional-grade confidence in the guaranteed nutrient analysis.
Key Specs
NPK Ratio
21-0-0
Secondary Nutrient
24% Sulfur (S)
Nitrogen Form
21% Ammonical Nitrogen (NH₄⁺)
Solubility
100% Water Soluble
Registration
CDFA Registered #2014005
Manufacturing Origin
Made in USA
Purity
Verified Low Heavy Metals
pH Effect
Acidifying
Features
- Provides rapid green growth and development.
- Essential sulfur supports chlorophyll formation.
- 100% soluble for immediate nutrient availability.
- Versatile use for various plant types.
- Helps acidify alkaline soils.
- CDFA Registered for quality assurance.
- Lab certified for nutrient content.
- Low heavy metals exceed EPA standards.
What customers say
Customers consistently highlight the exceptional effectiveness of this 21 0 0 formula, noting rapid and dramatic greening of lawns and plants. Reviewers frequently mention the high nitrogen content delivers quick results, making it a powerful tool for correcting deficiencies. The product is also praised for its excellent value, as a little goes a long way, offering significant coverage for the price. Users appreciate the granular consistency which aids in even spreading, though caution is advised due to its potency.
Know before you buy
This ratio provides a high concentration of nitrogen, which is the primary nutrient responsible for lush, green foliage and rapid vegetative growth. Because it contains no phosphorus or potassium, it is best used when your plants specifically need a nitrogen boost rather than a balanced, all-purpose fertilizer.
Yes, this product is specifically formulated to help acidify alkaline soils. The inclusion of 24% sulfur makes it an effective tool for gardeners looking to lower their soil pH to better support acid-loving plants like blueberries, azaleas, and rhododendrons.
As a 100% water-soluble powder, this fertilizer is designed to be dissolved in water and applied as either a soil drench or a foliar spray. This allows for immediate nutrient uptake by the roots or leaves, providing a quick response from your plants.
While it is versatile enough for lawns, vegetables, and shrubs, its acidifying effect means it is most beneficial for plants that thrive in lower pH environments. If you are growing plants that prefer neutral or alkaline soil, use this product sparingly and monitor your soil pH levels.
CDFA registration indicates that the product has been reviewed and verified by the California Department of Food and Agriculture to meet specific labeling and nutrient content standards. This provides an extra layer of assurance that the product contains the nutrients listed on the label.
This is a quick-release fertilizer. Because it is highly soluble, the nitrogen is readily available for plant uptake immediately after application, making it an ideal choice when you need to correct a nitrogen deficiency quickly.
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