What … Miracle-Gro is one of the most popular brands around when it comes to gardening... 2. Coffee Ground Fertilizer. Miracle-Gro Shake ‘N Feed Plant Food. The fertilizer we use for the blooming stage of growth is called Neptune’s Harvest Fish & Seaweed (2-3-1). Once our pepper plants have begun sprouting flowers, we switch to our second fertilizer. Additional tips for applying: One bottle of 9-4-9 fertilizer will feed about 400 square feet of space. Apply to plants every 7-14 days to help develop strong roots and grow high-quality peppers. Another great option to keep your peppers looking great all season long is the Miracle Gro’s Performance Organic Fertilizer. Fast facts on coffee ground fertilizer: Rose plant food. Soil acidifiers. Best Pepper Fertilizer Reviews 1. General Hydroponics Flora Combo Fertilizer. Stage Two Fertilizer for Peppers. If you’re growing peppers along with other plants or if you just like... 3. This fertilizer has much less nitrogen, but provides plenty of phosphate and potassium for pepper pod production.