The saying "an ounce of prevention is worth a pound of cure" is never more true than it is in lawn care. A new lawn that is properly cared for will grow in lush and green, preventing splotchy growth, inhibiting weeds and obviating the need for reseeding. Take especially good care of your new lawn for the first month and you will reap the benefits of your efforts for a long time.
Fertilize your new lawn frequently to encourage it to thicken and grow quickly. Use a lawn-starter fertilizer when you first plant, then start a schedule of fertilizing every 60 days with normal lawn fertilizer. According to Greg Pierce of Lawn Masters, Inc., the first treatment should be about 30 days before the start of the growing season to get a jump start on spring growth. Do not apply more fertilizer than recommended on the bag.
New lawns thrive with constant watering. For the first two weeks after planting your lawn, keep it damp all the time by watering it with a fine spray at least twice a day, once early in the morning and again early in the afternoon. After the lawn gets established, water it weekly, adding about 1 inch of water per week. You will know your lawn needs more water if it doesn't spring back up when you step on the grass.
Stay off your lawn as much as possible until the first mowing. After two weeks, give the lawn two days without water and, if there is now rain, mow the lawn. Only remove 1/3 of the blade, at most, to keep the lawn healthy.
Control weeds to keep your lawn healthy. When weeds appear in a new lawn, leave them be or remove them by hand until your lawn has become established. After three mowings, treat your lawn with a pre-emergent weed control. Apply it once in February and again in May.