Know what a healthy lawn looks like and inspect your grass frequently for insect or rodent damage while mowing. By using common turf treatments like fertilizing, weed control and aeration, you can grow grass that will be thick and healthy every year.
Fertilizer and Weed Control
To successfully combat weeds, fertilizers and weed-control sprays should be used on a scheduled basis. Most people multitask and use a "weed and feed" product. You will likely get better results if you take the extra time to apply the products separately. The best time for preventive weed control--use a pre-emergent herbicide--and the best time for fertilizing are rarely the same. Read the manufacturer's instructions or check online for your specific zone information. (Reference 1)
Just as you close up the pool and pack up the kids' toys, you need to treat your lawn to a fall cleanup. To winterize, reseed the barren or spotty areas on your lawn and fertilize with a winterizing (extra nitrogen) solution. Mow the lawn once more, down to an inch or so, before the first frost appears. Use the bag attachment to clear out leaves and cuttings that may pack down the grass and cause it to yellow over the colder months. (Reference 2)
Aeration involves making small holes in your lawn. Although it may seem counterproductive, aerating encourages your grass to grow deeper roots, which in turn makes it stronger. The more air and water that circulates around your lawn's roots, the better the growth of beneficial microorganisms in your soil. These microorganisms will eat the thatch and dried grass that may be stifling your lawn. Aerate your lawn twice a year for best results. (Reference 3)
A dead patch of grass could mean grubs have taken up residence in your lawn. Dig around and if you see the insects, get a curative product to kill them. Mixtures that contain carbaryl (Sevin) or trichlorfon (Dylox) work well when applied in the spring or fall. Use a sprinkler to water in the product so the treatment gets deep in the soil to the grubs.
If the idea of applying pesticides does not appeal to you, there are organic treatments for your lawn that work just as well. They need to be applied more often, though, because they lack the processed "slow release" function of manufactured fertilizers. Compost and mature are frequently used to improve soil quality. A combination that provides the necessary nutrients includes dried blood meal (phosphorus), cottonseed meal (nitrogen) and greensand (potassium and iron). (Reference 1)