Supply Solutions Ammonium Sulfate Fertilizer 21-0-0 (5 lb) — 24% Sulfur, Soil Acidifier for Acid-Loving Plants

Supply Solutions Ammonium Sulfate 21-0-0 +24% Sulfur is a water-soluble granular fertilizer that feeds nitrogen while lowering soil pH to support deep green growth and blooms in acid-loving plants.

Designed for gardeners who grow azaleas, rhododendrons, hydrangeas, blueberries, and acid-preferring lawns and trees, this 5-pound ammonium sulfate formula supplies concentrated ammonium nitrogen and sulfur to improve nutrient availability in alkaline or neutral soils. Easy to dissolve and apply, it helps direct nitrogen into plant uptake while providing sulfur to support healthy foliage color and flowering. Use it in soils that need modest acidification and targeted nitrogen without extra phosphorus or potassium.

How does this fertilizer help acid-loving plants perform better?

Ammonium sulfate supplies ammonium-based nitrogen that plants readily absorb and sulfur that slowly affects soil acidity, making some micronutrients more available. Together these actions can encourage greener leaves and more vigorous bloom development in species that prefer lower pH.

• Provides 21% nitrogen in ammonium form for rapid plant uptake.
• Contains 24% sulfur to gradually lower pH where needed.
• Formulated without added phosphorus or potash for targeted application.

When and how should I apply the 5 lb bag to my shrubs, trees, and lawn?

Apply during the active growing season according to plant type and soil test results. Dissolve granular product in water for foliar or root drench applications or broadcast lightly around root zones and water in for gradual uptake.

• Follow label rates; reduce frequency on sandy soils to avoid leaching.
• Use in spring and early summer for most flowering shrubs; split applications on lawns as needed.
• Water after application to move nutrients into the root zone.

Will this product change my soil pH and is it safe for container plants?

This ammonium sulfate acts as a mild acidifier; repeated use can lower pH over time, so monitor soil or potting mix pH when using in containers. For pots, use measured, diluted applications and avoid over-concentrating to prevent root stress.

• Gradual pH adjustment—best used when soil tests show higher pH than ideal.
• Suitable for containers when diluted and applied with care.
• Test soil pH periodically to prevent over-acidification.

How soluble and easy to use is this ammonium sulfate for home gardeners?

The granules dissolve readily in water so you can mix solutions for quick root feeding or foliar sprays and also broadcast evenly across garden beds. Its straightforward composition makes it adaptable for different application methods without additional filler nutrients.

• Good water solubility for quick dissolution and even distribution.
• Works in both liquid feed systems and dry broadcast applications.
• Minimal additives—simple N and S formula for focused results.

Who is this for: Supply Solutions Ammonium Sulfate 21-0-0 +24% Sulfur is intended for home gardeners, hobby farmers, and landscapers who grow acid-loving ornamentals, berries, or turf and want a dependable nitrogen source that can also help lower soil pH. It’s especially useful when soil tests indicate a need for ammonium nitrogen and additional sulfur without extra phosphorus or potassium. Use cautiously on sensitive plants and follow soil test recommendations for best outcomes.

Ingredients

Ammonium Sulfate Fertilizer