How does lawn fertilization work? As we fertilize lawns, a lot is going on in your grass to contribute to thick, bright, green grass. Choosing fertilizer yourself can be overwhelming. There are hundreds of off-the-shelf fertilizers offered. Stores and companies tend to market as if there is a one-size-fits-all solution to fertilizing, but there really isn’t. Fertilizer has mix of several components. Nitrogen, Phosphorus and Potassium are all present in fertilizer. These ingredients contribute to healthy, green grass, strong roots and strength. Nitrogen encourages the production of chlorophyll, which helps healthy leaf growth. Phosphorous helps the roots grow strong and deep. Potassium provides your lawn with strength to resist disease and drought. If you do buy a bag of fertilizer in the store, you’ll see a number system on the bag telling you the mix of components in that bag. If you have a 20-15-5 ratio, you have 20% Nitrogen, 15% Phosphorous and 5% Potassium. That doesn’t equal 100%, the remaining materials are made up of inert materials and trace elements. The Nitrogen, with the help of chlorophyll promotes photosynthesis, gives your grass that lush green look. As stated above, it helps the leaf growth of the grass, which is what provides a great visual appearance.