Ammonium Sulfate vs Urea: Key Differences for Higher Crop Yields
Ammonium Sulfate is a granulated salt that supplies both nitrogen and sulfur; Urea is a white prill made of 46 % pure nitrogen. They feed crops, but they do it differently.
Walk any farm-supply aisle and you’ll see 50-lb bags stacked side-by-side. Farmers grab whichever is cheapest that week, then wonder why the corn turns yellow or the wheat stalls. The mix-up costs bushels, not pennies.
Key Differences
Ammonium Sulfate releases acidic nitrogen and 24 % sulfur, perfect for alkaline soils. Urea packs twice the nitrogen per pound, yet it volatilizes fast in warm, moist fields if not watered in quickly.
Which One Should You Choose?
Need sulfur and your pH is above 7? Reach for Ammonium Sulfate. Chasing rapid top growth on neutral, irrigated land? Urea gives more N per dollar, but only if rain or irrigation follows within 48 hours.
Can I blend them together?
Yes, but only in the spreader; store the mix dry to prevent caking and ammonia loss.
Which is safer for seedlings?
Urea at low rates; Ammonium Sulfate’s salt effect can burn tender roots if over-applied.