Mow the lawn properly
For the best appearance and good health of lawn grass, mow high using a sharp blade. A dull blade will tear rather than cut the lawn leaving a ragged end on the grass blades that cast a dull haze over the lawn. That ragged edge also leaves the grass more vulnerable to disease. Depending on the size of the lawn, a mower blade becomes dull after one or two seasons and should be sharpened or replaced every year or two. Grass that is dense and cut over 2-inches tall has few weeds and serves as habitat for ants, spiders, and ground beetles which keep the pest insects of a lawn in check. Tall grass shades the soil reducing evaporation of moisture and will not burn out in the heat of summer. Set the mower for 2 to 2-1/2 inches in the spring and fall and raise it to 3 inches in summer.
Use only slow release granular fertilizer
Quick release nitrogen fertilizers need to be applied three or four times a year in order to be effective. High in salts, the increased salinity burns turf roots and repels the valuable earthworms and kill many of the beneficial soil microbes. Slow release nitrogen fertilizer needs to be applied only once or twice a year and will not hurt the soil critters. Use slow release nitrogen fertilizer in the spring and again in the fall for a few years, but if you are taking care of your soil, you can drop back to a single application in the fall, or split the application putting down half the recommended amount in spring and half in fall.
Avoid watering too much or too little
The key questions in watering the lawn are: When does the grass need to be watered? and How much do I need to water?. When you walk over a lawn that is mowed tall, you will leave temporary footprints. If the footprints disappear with the grass popping back upright within a minute or two the grass has enough water. If the foot prints last more than 3 or 4 minutes, the lawn needs to be watered. In spring and fall between your hose and Mother Nature, give the lawn an inch of water each week. Lawns need two inches a week in the heat of the summer. An empty tuna fish can is one inch deep so put a few empty tuna cans out in the pattern of your sprinkler and track the time to see how long it takes to fill the cans and you can quickly figure how to deliver an accurate amount of water to the lawn. A rain gauge will help you keep track of Mother Natures contribution.
Avoid using any broad spectrum insecticides
A lawn that is dense and mowed tall is likely to be inhabited by a healthy population of beneficial insects, including ants, spiders, and ground beetles, seldom has any problems from fleas, grubs, sod webworms, chinch bugs or any other lawn grass insect pest. If you routinely use a broad spectrum insecticide each year, you will kill all the good guys along with the bad guys. If the grass is mowed tall and kept dense from overseeding, those beneficial insects will eliminate the need for the annual use of the insecticide.
Spread lime only if needed in late fall, not in the spring
Use lime on the lawn only if you are sure that your soil is acidic enough to justify it. A soil test is the only accurate way to tell. Contact your County Extension Service to get a soil test kit and related information. If you do apply lime, use a granular lime product in October or even in November. It takes six months for granular lime to break down sufficiently to be helpful to the grass plants.
Buy only the highest quality grass seed
Only the top quality grass seed includes varieties that have been bred with good disease resistance, look good, and are drought resistant. When you buy the high-end brands, you can trust the grass seed companies to give you the right mixture for the northeast. Buy full sun mix if your lawn gets over 6 hours of sun a day. Use a shade mixture if your lawn gets 3 to 6 hours of sun a day. Any lawn getting less than 3 hours of sun a day must be overseeded every spring to look even average for the season.
Get rid of grubs and moles by growing good soil
Grubs and moles are only a problem in lawns that are compacted and have turf with roots only two inches deep. If you add organic matter to the soil under your turf on a yearly basis, the earthworms and soil microbes lower the level of compaction over time, so after 3 to 5 years, the grubs and moles are working down at the 4 to 6 inch depth and are not evident in your lawn.