Of course, there are many different kinds of fertilizer with different uses and applications. However, one of the most commonly used is the 15-15-15 fertilizer. What is 15-15-15 fertilizer used for? Fertilizers with an NPK ratio of 15-15-15 are used to promote strong root growth, healthy foliage, encourage blooming, and improve general plant health. It can be used on a wide range of plants, including flowers, vegetables, fruit trees, berry bushes, and ornamentals. It’s considered an excellent nutrient for plants. It works to maintain the overall health of your soil and garden, and it’s renowned as an efficient and reliable fertilizer for different kinds of plants and trees. This is why it’s famous among home garden owners, who focus on having beautiful blooms in their backyard.