Left alone, grass has no problem providing its own seed and replenishing itself. A manicured lawn often doesn’t have that ability because most, if not all, of the seeds are chopped off before they mature by repeated mowing. That’s why it’s important to reseed your lawn from time to time, especially if it gets a lot of wear and tear.
When you should reseed your lawn depends on geography. Here’s why fall is the best time for reseeding lawn in the North. For starters, that’s when grass normally matures its own crop of seeds, if left to its own devices. An ideal time would be at least 45 days before the first average fall frost date. Unlike spring, the soil is already warmed up, encouraging germination.
Take advantage of the season, when cooler temperatures and more consistent soil moisture make things less stressful for delicate, newly forming grass blades. Fall rains tend to be gentler than those in spring, allowing the water to soak into the soil where it will do some good. In addition, less irrigation is required because the hottest weather will have passed. Weeds and pests are less prevalent, too, lessening competition and stress on new grass.
In the South, seeding a new lawn is generally done in spring, but fall is a good time for overseeding an existing lawn. That’s when warm-season grasses are supplanted by cool-season grasses, ensuring winter color when the former go dormant. Wait until mid to late fall, when nighttime temperatures are consistently below 65 degrees F and the warm-season turf begins to lose color.
If you are reseeding a lawn, don’t make the mistake of tossing seed on bare, hard-packed ground—most of it won’t take root in such conditions. Prepare the soil first. Use a heavy-tine garden rake to remove thatch and scratch the surface of the soil deeply to make germination easier. Sow the seed and use a roller to press seed into contact with the soil, then cover lightly with a dusting of peat moss or screened compost.
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