Fertilizer is a substance added to soil or plants to provide essential nutrients that help them grow. It can be made from natural sources, like animal manure or compost, or from synthetic materials. By supplying nutrients such as nitrogen, phosphorus, and potassium, fertilizers boost plant health and increase crop yields. Farmers and gardeners use fertilizers to ensure their plants receive the right balance of nutrients. Applying the correct type and amount of fertilizer can lead to healthier plants and better harvests. However, it's important to use fertilizers responsibly to avoid harming the environment or causing water pollution.