What Could Be Causing My Grass to Die?

Fertilizer Burn

• Fertilizers are intended to help your lawn grow thicker, greener and healthier. However, too much fertilizer can have the opposite effect. Always use fertilizer that is formulated for your type of grass, and never use more than the manufacturer suggests. Too much, or the wrong type, can dehydrate, or burn, the grass and eventually kill it.

Insects

• Insects can draw the life from your lawn, so search for potential culprits. Inspect blades of grass, grass clippings and roots in dead and dying areas. Compare your findings with similar areas of healthy grass. Insects found throughout healthy and unhealthy grass are probably harmless, and your dying grass might have another cause. However, if insects are concentrated in dead and dying areas, they are probably the cause of the problem. Control them with a broad-spectrum insecticide that is suitable for your climate and type of grass.

Fungus

• There are many fungi that create patchy and widespread damage to lawns. Leaf spot, melting out and powdery mildew can affect large areas. Necrotic ring spot, sclerotinia dollar spot and pythium blight create smaller patches of dying grass. Some fungi leave obvious dusty or slimy residue on the lawn. Other types are harder to spot, so the only clue might be dying grass. Lawn care specialists can discern whether your lawn harbors fungi and help with identification. With that knowledge, a focused treatment plan can kill the fungus. Prevent fungus by raking the lawn regularly to prevent dead grass, also called thatch, buildup. Water appropriately for your type of grass, soil condition and climate, because fungi thrive in damp areas.

Improper Mowing

• Mow your lawn based on its condition and growth, not on a rigid, weekly schedule. In hot weather with plenty of rain, grass can grow faster than usual; weekly mowing might not be enough. Cutting off more than one-third of the height at a time weakens the grass, making it susceptible to disease and other problems. In drought conditions, mowing too often or too short can kill an already weak lawn. If you arrive home from a vacation to find that your lawn resembles a hayfield, mow it on the highest possible setting. Lower the mower deck slightly for each future mowing, and gradually bring your lawn under control.