Using Ammonium Nitrate on Mondo Grass: Why a Complete Fertilizer Is Better

A gardener asked about dissolving ammonium nitrate in water to spray on mondo grass instead of using a balanced fertilizer. Here’s why that’s not ideal.

The Nutrient Gap

Ammonium nitrate supplies only nitrogen (34-0-0). Plants also need phosphorus for root development and potassium for stress tolerance and disease resistance. Mondo grass, like all plants, requires all three macronutrients.

Better Approach

• Choose a complete fertilizer such as 20-10-10 or a turf-grade 29-3-4.
• Apply granular product by hand—sprinkle lightly around each clump—then water in. No need to pre-dissolve.
• If you must use a liquid, a 200–400 ppm solution (½–1 tsp ammonium nitrate per gallon) works, but you’re still missing P and K.

Application Tip

For small areas, a slow-release 10-10-10 or 14-14-14 applied once in spring eliminates the need for frequent feeding and reduces burn risk.