FoxFarm Happy Frog Citrus and Avocado Fertilizer- OMRI Listed Citrus Fertilizer, Slow-Release Nitrogen, Calcium & Sulfur for Citrus & Avocado Trees – 4 lb. Manufacturer: FoxFarm. Included Components: FoxFarm Happy Frog Citrus & Avocado Fertilizer – Formula for Lemons, Oranges, Av.