|I have a neighbor with a crabgrass lawn.|
|I agree with your thoughts of overseeding your lawn. The University recommends the following grass types for your area:
Kentucky Bluegrass: 'Georgetown', 'Award', 'Midnight', 'Blackstone' or 'Glade'.
Perennial Ryegrass: 'Palmer III,' 'Calypso II', 'Secretariat', 'Panther', or 'Brightstar'.
I wouldn't recommend intentionally planting clover in your lawn - it can become weedy and it will be very difficult to remove if you decide you don't like it - unless you are looking for an alternative to turfgrass. If so, one consideration is to convert your existing lawn into a wild lawn. Set your mower blades as high as four inches to encourage species of low-growing wild ground covers?such as violets, cinquefoil, blue-and-white-flowered speedwell, heal-all and white clover?to take hold and bloom. While you can introduce some of these to your lawn by transplanting, many seeds are already in your lawn and others will arrive naturally as seeds floating on the air. They will colonize your lawn quickly and their blooms and leaves will feed beneficial insects.
A natural meadow, a taller option, requires no feeding or watering after the seeds and young plants are established. It needs mowing only once a year (in late winter, to avoid destroying eggs and larvae of butterflies and beneficial insects). To maximize success with a meadow, seed or plant an area in full sun with a variety of annual and perennial flowers native to your region. The following wildflowers grow in most areas of the country and attract a variety of creatures: goldenrod, milkweed, butterfly weed, asters, coneflowers, sunflowers, yarrow, buttercups, bee balm, phlox, tickseed and blazing stars. (Ask your local native-plant society or extension agent which plants are native to your area and which will thrive for you.)
Another option is to replace your carpet of fescue, Kentucky bluegrass or crabgrass with a ground cover. Such covers?especially dense, evergreen varieties?provide a beautiful and carefree alternative to a conventional lawn. Besides providing food and shelter for wildlife, they define, separate or unify areas in the landscape as effectively as a green velvet lawn. When choosing a ground cover appropriate to your region, find out how quickly it grows, whether it is best suited to sun or shade and how well it can withstand foot traffic.
There are several native ground covers that remain evergreen or semi-evergreen. These include partridgeberry, lowbush blueberry, wintergreen, bearberry, wild ginger, wild strawberry and moss phlox. Easy-to-grow, non-native evergreen ground covers include creeping thyme, bugleweed, Roman chamomile and St. John?s wort. (Check with your local nursery to find out which species grow best in your region.) For fastest results with ground covers, reduce the recommended space between plants by half.
Hope this information gives you food for thought. Best wishes with your landscape!