Sulfur Prills OMRI

Slow-Release Elemental Sulfur — a Gentle, Long-Lasting Soil Acidifier

Old Cobblers Farm Sulfur Prills are a slow-release soil acidifier made from 100% elemental sulfur. They gradually lower soil pH to create the acidic conditions that blueberries, azaleas, rhododendrons and other acid-loving plants prefer. Because the sulfur must first be converted in the soil by naturally occurring bacteria, the acidification is gradual and long-lasting — which lowers the risk of over-acidifying compared with fast-acting products.

As the soil becomes more acidic, certain nutrients — iron in particular — become more available to acid-loving plants, which is why correcting pH often greens up plants that were struggling in alkaline soil. Elemental sulfur also supplies sulfur, a secondary plant nutrient. It is a soil amendment rather than a complete fertilizer, so pair it with a fertilizer for feeding.

The prilled form is low-dust and easy to spread or work into the soil. Always start with a soil test to set the right rate, work the prills in, and water. Acidification develops over weeks to months, and a single application typically lasts a good while — reapply only as a soil test indicates.

Where to use it: blueberries, azaleas, rhododendrons and other acid-loving plants, plus general soil-test-guided pH lowering in beds, vegetable gardens and lawns.

Key Benefits

•  Lowers Soil pH Gradually: Creates acidic conditions for acid-loving plants — slowly and steadily.

•  Slow-Release & Long-Lasting: Converts in the soil over time, so effects are consistent and durable.

•  Lower Over-Acidification Risk: The gradual action makes it harder to overshoot than fast-acting acidifiers.

•  Improves Iron Availability: Acidic soil makes nutrients like iron more available to acid-loving plants.

•  Supplies Sulfur: Elemental sulfur is also a secondary plant nutrient.

•  Low-Dust Prills: The prilled form spreads cleanly and works into the soil easily.

•  Generally Organic-Accepted: Elemental sulfur is a material commonly allowed in organic gardening (confirm certification).

Best Uses

•  Blueberries and other acid-loving fruit

•  Azaleas, rhododendrons and acid-loving ornamentals

•  Lowering pH in alkaline garden beds

•  Vegetable beds at preparation (soil-test guided)

•  Lawns on alkaline or hard-water soils

•  Gardeners and growers wanting gradual, low-risk acidification

Important Notes / Safety

•  Soil-Test First: Test your soil pH before applying to set the right rate, and re-test before reapplying.

•  It Works Gradually: Acidification develops over weeks to months as soil bacteria convert the sulfur — don’t expect an immediate pH change.

•  Lower Risk, Not Zero: The slow release reduces the chance of over-acidifying, but you can still overshoot with heavy or repeated use — follow the rate and re-test.

•  It’s an Amendment, Not a Fertilizer: It adjusts pH and supplies sulfur, but has no nitrogen, phosphorus or potassium — feed separately.

•  Reapply Sparingly: A single application lasts a good while; the copy suggests every 2–3 years — let a soil test guide reapplication.

•  Handle & Store Safely: Keep prills dry and away from heat and ignition sources (sulfur dust is combustible). Wash hands after handling and keep away from children and pets.

Why Choose Old Cobblers Farm™?

When you want to lower soil pH without the risk of overshooting, elemental sulfur is the gentle, dependable choice. Our Sulfur Prills convert slowly in the soil for steady, long-lasting acidification — ideal for blueberries, azaleas and other acid-lovers — and the low-dust prills are easy to apply. Soil-test first, work them in, and let time do the rest.