For something so passive, the lawn has a remarkable ability to polarize.
At one end of the turf wars, the hobbyist is driven to outdo all others with the greenest, thickest, most groomed greensward in the neighborhood.
At the other end, the environmentalist views grass and its appetite for pesticides, fertilizers and water as diabolical.
For the rest of us, the lawn speaks in a different way: "Help!"
Now is the best time for lawn fixing, especially for seeding preferred cool-season fescues. It might seem more intuitive to seed in the spring, when everything is growing, but spring seedlings can be too frail to handle the rigors of summer. Fall-started grass will have developed more fully before the stresses of next year's growing season.
Here is some advice from a few turf experts: Debra Ricigliano of the Maryland Home and Garden Information Center; Dwayne Parris of Chapel Valley Landscape Co. in Woodbine, Md.; Murray Cook of the Brickman Group's Sports Turf Services in Columbia, Md.; Jody Fetzer of Hillwood Estate, Museum and Gardens in Washington, D.C.; and Scott Steinfeldt of Chanticleer Garden in Wayne, Pa.
If you are faced with a declining lawn and a desire to fix it yourself, you have three options: complete renovation, overseeding or patching bare spots.
Renovating the lawn
If your lawn is thin and overrun with weeds, it might be time to start again. A complete renovation gives you a chance to deal with perennial weeds and reverse soil compaction, improve the topsoil and switch to a better variety of turfgrass. The standard advice is that if your lawn is more than half weeds, complete renovation is in order.
The size of the lawn dictates the approach. A small urban lawn can be handled easily with manual tools, but for anything more than 2,000 square feet, you need mechanical help.
You can spray your old lawn with glyphosate (most economically as concentrate diluted in a sprayer) and heed all the label precautions. It is too late to use more persistent herbicides, which would interfere with grass-seedling growth. This might include glyphosate with added herbicidal ingredients. After spraying with glyphosate, wait seven days, and then dig up or rototill the dead lawn. Alternatively, you can dig up the live lawn, separate the vegetation and add the turf remnants to the compost pile, and sow seed without the wait.
Before laying the seed, add two to four inches of soil amendments. A mixture of topsoil, organic matter and washed sand will do wonders. Incorporate the mix into the existing soil before raking smooth. Add starter fertilizer at the recommended label rate.
Overseeding the lawn
If the lawn is beginning to decline but still looks OK, you can overseed to bring it back to full vigor. Overseeding probably is the most misunderstood aspect of lawn repair. You can't just spread seed on an unprepared lawn and expect it to germinate. It needs good soil contact to grow. One of the most effective ways to create that is to use a core aerator, designed primarily to open compacted soil but effective, too, in exposing the soil surface for seeding. The thinner and weedier the lawn, the more you aerate. After aeration, top-dress the lawn with organic matter, such as Leafgro. The raked layer should be 1/4 to 1/2 inch thick. That requires four to eight cubic yards per 5,000 square feet.
Follow grass-seeding rates on the label. You don't want to put down too little, but too much inhibits healthy seedling growth.
Patching the lawn
The third option is to patch areas that are thin or overrun with weeds. Think of it as a complete renovation in a small area. Fashion the areas into well-defined squares or rectangles. Lawns can be renovated through a combination of patching and overseeding.
Rolling will help with seed-to-soil contact. The seed should be misted once or twice a day (not heavily watered) until germination, especially in a dry fall. Keep people and pets off newly seeded lawns until they are established. A light, thinly spaced mulch of straw, not hay, will help retain moisture and reduce bird feeding. Some pros worry about weed seeds in straw and recommend products that combine an inert mulch with starter fertilizer.
Be patient. It takes two to three weeks for tall fescue to germinate, longer for bluegrass. Mow at three inches once the seedlings reach four inches. Fit a new mower blade before doing this, and don't use herbicides until spring.
Don't allow autumn leaves to pile up and mat on seedling lawns. A leaf blower is less likely to disturb soil than a rake.
County extension agents recommend soil tests before lawn renovation so you can add the right amounts of fertilizer, organic matter and lime as part of the process. However, if you want to renovate your lawn now, it's too late to wait for soil-test results. Take soil samples before you start your lawn renovation. If the results recommend additional fertilizing or liming, address those deficiencies once your new lawn has grown this fall. You can lay fall fertilizer until early December, and lime at any time.