Fertilizer Tips Use slow release fertilizer. Most store bought fertilizers have a very small amount of slow release product, usually less than five percent (5%). Grow Pros uses at least thirty percent (30%) slow release products. This ensures your fertilizer will last until the next treatment. Iron gives your lawn a deep green color. Grow Pros puts down iron with every application of fertilizer. Watering Tips Your lawn needs an inch and a half of water a week, either from...