DIY Fertilizer Blend: Substituting 5-10-15 with Farm-Grade Ingredients

Your soil test calls for 5-10-15 fertilizer, but garden centers only stock lawn blends. No problem—you can mix an equivalent ratio using three farm-grade products available at most nurseries.

The Recipe

In a plastic tub, combine:

• ½ lb ammonium nitrate (34-0-0)
• 1 lb triple superphosphate (0-46-0)
• 1 lb muriate of potash (0-0-60)

Why It Works

The result is a 7-18-24 analysis. The nutrient ratio (1-2.6-3.4) closely matches 5-10-15's 1-2-3. It's more concentrated, so apply at ½ to ⅔ the soil test's recommended rate. Always water in thoroughly.

Practical Tips

Wear gloves and a dust mask. Mix outdoors. Store leftovers in a sealed, labeled container away from moisture. This blend gives you the phosphorus and potassium your vegetables need for root and fruit development, plus nitrogen for later growth spurts.