Fertilizing for Deep Root Growth Growing deep, dense grass roots A lawn is actually millions of grass plants that have changing nutritional needs depending on the season. Lawn care experts recommend fertilization when the grass plant is growing to maintain vitality, structure and root strength. A strong root system produces a healthy, thick, weed free lawn. Cool season grasses grow roots in the fall and until the ground freezes. A program of weed and feed in spring and feeding in fall is beneficial for your lawn. Seasonal root growth of turfgrasses Cool season turfgrasses grow roots most vigorously during spring and fall. Root growth, as well as top growth, slows with the hot, dry weather of summer. GreenView Fairway Formula Fertilizers contain the same advanced nitrogen technology as used on championship golf courses. GreenView Fairway Formula Grass Seed are NTEP rated top quality varieties, specifically bred for disease, insect and drought resistance.