If Mother Nature doesn't water your lawn regularly, you'll need to do it. Instead of giving your lawn a quick drink every day or two, water it infrequently but for a longer time so the water reaches a depth of 4 to 6 in. This encourages deep root growth and healthy, drought-tolerant grass. Turf grass needs an inch or two of water (including rainfall) each week to thrive. Use a rain gauge to determine how much additional watering is needed. For best results, water in the early morning or early evening, when there's typically less wind and heat. Keep in mind that evening watering has one disadvantage: Wet grass is more susceptible to diseases during cooler nighttime temperatures.
Most lawns do just fine with one dose of fertilizer each year, but you'll achieve more lush growth if you apply two. Read instructions on a few brands of fertilizer before choosing which type is best. Feed grass during its active growing season. For example, fertilize warm-season grasses such as Bermuda, Buffalo, St. Augustine and zoysia in the early spring or summer. Fertilize cool-season grasses such as Kentucky bluegrass, perennial ryegrass and fine fescue in early spring and late fall. If you plan to fertilize only once a year, choose spring for warm-season grasses and fall for cool. Apply fertilizer when the grass is dry, and give it a good dose of water to move nutrients into the soil and to prevent the fertilizer from burning the grass tips.
When grass grows fast, as it does each spring, you'll need to mow more frequently than in the hot summer, when growth slows down. A good rule of thumb: Don't remove more than one third of the grass blade at one time. To control weeds and reduce watering, keep grass length between 2 and 3 in. Leave grass clippings on the lawn because they'll decompose and add nitrogen to the soil.
If you don't have many weeds, you can pull them by hand; just make sure you pull out the roots. To control heavier infestations, apply a pre-emergence herbicide in early spring, just before weed seeds sprout. Pre-emergence herbicides don't work once plants begin to grow. To effectively rid your lawn of broadleaf menaces such as dandelions and clover, use a post-emergence weed killer. Apply either a spray-on broadleaf weed killer or a weed-and-feed product when your lawn is wet and the grass has a high growth rate (during spring or fall, depending on grass type).
Aerate and dethatch
Even the healthiest lawn can benefit from aerating. To prevent soil compaction and allow for better root development in heavy soils, aerate your lawn every other year. Aerators punch holes that allow air and moisture to penetrate the soil. You can rent a core aerator, which removes soil plugs that decompose on top of the grass, from a home or garden store. Don't use tine aerators and strap-on shoe spikes; they compress soil in the area around the tines, adding to compaction problems.
Water your lawn well before aerating. Like fertilizing, aerating is best done when your grass has a high growth rate.
Dethatching removes the layer of roots, stems and other organic matter that builds up between the grass and the soil line. Less than 1/2 in. of thatch is not a problem, but anything more prevents nutrients and water from getting to a lawn's root system. You can remove thatch with a dethatching rake, which is equipped with sharp tines, or save your arms some work and rent a dethatcher or power rake.
Overseed, patch and replace
If your once enviably lush lawn becomes plagued by brown spots, sparsely covered sections or bare patches, you must first determine what's causing the unsightly areas. Your local extension office can help diagnose the problem. Pet urine, fertilizer spills, insect damage, weed killer drifting from other spots, too much or too little water and closely cropped mowing all can cause damage.
Once you know what you're up against, try repair strategies such as overseeding, plugging or sprigging for small spots. Overseeding works well where grass is thin but still green. When overseeding, make sure the seeds make contact with the soil. Mow grass close to the ground; then rough up the spot with a rake. Spread seeds with a drop spreader or by hand.
Plugs and sprigs work best when patching bare areas with warm-season grasses such as St. Augustine or Bermuda. Sprigs are usually soilless strands of grass, and plugs are small chunks of sod. Before planting, prepare the soil by first clearing the area of old grass and weeds and then tilling and amending with compost or other organic matter. If your lawn is diseased, weed-infested or more than 50 percent bare, consider replacing it with new sod.
TURF TIP: CHOOSE THE RIGHT GRASS
To simplify lawn care, start by planting the right grass for your area. Cool-season grasses such as Kentucky bluegrass and perennial ryegrass thrive in cold climates, whereas warm-season grasses such as Bermuda and St. Augustine do best in the South and Southwest.
TURF TIP: CONSIDER GROUND COVERS
It's challenging to grow grass in the shade. Even when seed is labeled for shade, it won't do well in deep, dark shade; it needs some dappled light to thrive. If you have a shady spot where grass won't grow, consider ground covers such as periwinkle, sweet violet and lily-of-the-valley instead. Use mulch between plants to reduce weeds. Ground covers naturally spread quickly — sometimes too quickly. Check with a local nursery or cooperative extension office to find out which ground covers are invasive.
TURF TIP: WEATHERING THE DROUGHT
In many states, summer watering restrictions are common. To ease stress on your lawn between designated watering times, water deeply so the soil is wet to a depth of 6 in., reduce fertilizers (especially nitrogen) and keep grass height at about 3 in. Buffalo grass, Bermuda grass and some zoysia grasses can survive with no water for long periods of time.
About the Author: Meleah Maynard writes about gardening and is based in Minneapolis, Minnesota.