Mother Earth Nitro Bat Bat Guano is a single-ingredient bat guano supplemental fertilizer. From our cave to your garden, Mother Earth Nitro Bat Bat Guano 5-3-1 is sure to become your garden?s new best friend. This dry fertilizer is great for oversized and fast-growing plants of all kinds during the vegetative stage. Thanks to its high nitrogen content and ample supply of phosphorus, bat guano has been heralded for centuries as a secret weapon for keeping even the hungriest of plants satiated. Use this powerful single-ingredient fertilizer biweekly for heavy feeders, or monthly for standard houseplants.