EVOLVE Dog Spot Prevent granular fertilizer is derived from feather meal, bone meal, calcium sulphate, kelp and sulphate of potash. Did you know that your lawn prefers a pH range of 6.8 to 7.5? Depending on where you are, soil typically has a pH of 7.3 to 7.8 (which your lawn can adapt to). When dog urine, which typically has a pH of 8 or higher, is introduced to the soil your lawn cannot tolerate the dramatic pH increase in that concentrated area. EVOLVE Organic Dog Spot Prevent works for your lawn in two ways: 1. EVOLVE Organic Dog Spot Prevent reduces the overall pH of your soil to approximately 7 so that the impact of the higher pH urine has much less of an impact to your lawn. 2. EVOLVE Organic Dog Spot Prevent also absorbs urine on impact and will then slowly introduce it to your soil further reducing its ability to increase the pH of your soil. In order to lower and maintain the pH of your soil, EVOLVE Organic Dog Spot Prevent has to be applied three times per year for best results - spring, mid summer and fall.