Important Notice: Our web hosting provider recently started charging us for additional visits, which was unexpected. In response, we're seeking donations. Depending on the situation, we may explore different monetization options for our Community and Expert Contributors. It's crucial to provide more returns for their expertise and offer more Expert Validated Answers or AI Validated Answers. Learn more about our hosting issue here.
The NPK numbers on a bag of fertilizer represents the percentage of each nutrient in the bag. A 40 lb bag of 15-5-10 chemical (salt) fertilizer contains 15% nitrogen, 5% phosphate and 10% potassium for a total nutrient content of 30%. The other 70% consists of filler material, usually an inert material like clay.
