Late August into early September is the ideal time for seeding new lawns and renovating existing lawns in need of repair. When lawns are not in desirable condition and need some attention, where does the process start?

Two factors have a major influence in lawn renovation plans. First, how much desirable grass remains on the site? If the level is significant, then focus on overseeding to thicken lawns, often combined with management practice modifications. On the other hand, if little if any desirable grass remains, then total renovation, or starting over, is the route to go.

Underlying soil conditions is the second major influence on renovation plans. If your soil is good, just focus on overseeding. Poor soil conditions need to be addressed or newly seeded lawns will most likely fail, so total renovation is the most logical route to take if your soil is less than ideal.

When seeding lawns or overseeding existing lawns, good seed to soil contact is essential for success. Overseeding into existing grasses requires some type of cultural practice to help ensure seeds hit the soil. Hand raking works for small areas. Equipment such as power rakes or vertical mowers help in larger areas. Slit seeders are highly effective. Check rental agencies or landscape services for equipment to meet your needs.

Total renovation and starting new lawns are close to the same process. Perennial weeds need to be removed or killed with a nonselective herbicide that allows reseeding quickly afterwards. Do this in the next two weeks so all vegetation is dead by late August.

Work the soil to a depth of six inches and add organic materials such as compost to improve both clay and sandy soils. The goal is to have 4 to 6 inches of well-prepared soil prior to seeding or sodding. Take the time and effort now, as poorly prepared soil is commonly why lawns fail.

Seed lawns in late August or early September. Choose high quality blends of grasses adapted to either full sun or shade, depending on the site. Look for named cultivars on seed package labels; they cost a little more but are worth it.

Overseeding existing lawn areas creates a few management dilemmas. Early September is a key time for both lawn fertilization and broadleaf weed control with herbicides. Unfortunately, herbicides will damage or kill young grass seedlings, as can a full rate of nitrogen fertilizer. When overseeding lawn areas, management practices should focus on seedlings, not established turf.