When looking for a low maintenance grass consider using fescues. Fine-leaf fescues, especially sheep fescue and hard fescue, grow very slowly, require little to no fertilizer, do well in acidic and shady sites. Some cultivars (varieties) have endophytes which are beneficial fungi that live in the leaf sheath of the grass and produce chemicals that deter surface-feeding insects such as chinch bugs and sod webworm. Keep in mind fine fescues do have their problems: they can’t hold up to lots of traffic or wear and tear, they can take on a “brown haze” appearance under full sun and dry conditions without irrigation and they are susceptible to white grub infestations. You can have an excellent fine fescue lawn if you have irrigation.
Tall fescue is another grass to consider for home lawns and also contains endophytes. Breeders have developed exceptionally dark green cultivars that are extremely heat and drought tolerant. Because of its wide blade and upright growth habit it doesn’t blend well with Kentucky bluegrass or perennial ryegrass so it should make up 90% of the grass mixture. Tall fescue has a bunch type growth habit which means it can be clumpy in appearance. It will require overseeding to be competitive where there is a lot of traffic. Tall fescue requires more frequent mowing and is susceptible to brown patch and Pythium diseases. Tall Fescue is most successful when established from seed in early August. It performs best when properly fertilized with nitrogen.
Perennial ryegrass germinates very quickly and can provide uniform lawn within two weeks. It thrives in full sun, requires well-drained soils and will require moderate to high fertilization. Perennial ryegrass is susceptible to a few diseases (red thread, rust, brown patch and Pythium blight) especially when not maintained properly. It is not well adapted to shade or drought conditions and because it is a bunch grass overseeding may be needed any time it becomes thin.
Kentucky bluegrass is the most common cool season grass used in home lawns and one that is associated with providing a “high quality” lawn.  It spreads by underground stems (rhizomes) which allows it to form a nice dense sod and one that can recover from damage.

Overseeding for healthy lawns and clean water

Although the best time to seed lawns is in late summer/early fall bare spots should be over-seeded regularly to reduce the chance of soil erosion, improve water infiltration, reduce weed invasion and use fertilizer more efficiently. This is the time when you can introduce new and improved varieties that may have more pest resistance, better fertilizer efficiency, lower water requirement, may be darker in color or have other desirable attributes.
First be sure to match the grass with your lawn situation and maintenance program.

	Tall fescue	Fine fescue	Perennial rye	Kentucky blue
Shade tolerance	good	excellent	poor	poor
Drought tolerance	more	more	less	less
Fertilizer need	little	little	med-high	med-high

Kentucky bluegrass thrives in full sun and well drained fertile soils. It should be fertilized regularly and will require irrigation to avoid summer dormancy when warm, dry conditions exist. Kentucky bluegrass is susceptible to leafspot, dollar spot, summer patch and necrotic ringspot.
Fortunately there are many pest-resistant cultivars and very dark green cultivars available. Keep in mind that if you need quick germination Kentucky bluegrass is not the grass to use. It usually takes more than two weeks to germinate and many weeks to produce a dense turf. When establishing a lawn Kentucky bluegrass needs to make up at least 80% or more of the mix when seeded with fast germinating grasses like perennial ryegrass to remain the predominant grass.
Overseeding rates should be 4-6 lbs for perennial ryegrass, 6-8 lbs for tall fescue, 2-4 lbs for fine fescue and 1-2 lbs for Kentucky bluegrass per 1,000 square feet. 
Establishment seeding rates will vary depending on seeding mixtures and situations.
For shady sites plant:
a 100% fine fescue blend at 4-5 lbs. per 1,000 square feet.
For sunny low-maintenance lawns plant:
100% tall fescue blend at 7-10 lbs. per 1,000 square feet.
or
65% or more fine fescue blend +
15% or less perennial ryegrass +
20% or less Kentucky bluegrass blend at 4-5 lbs. per 1,000 square feet
For sunny medium-high maintenance lawns plant:
65% or more Kentucky bluegrass blend +
15% or less perennial ryegrass +
20% fine fescue at 4-5 lbs. per 1,000 square feet.

The best period to seed is when temperatures are cool and soils are warm and moist.  Scalp the turf low and over-seed with improved varieties at recommended rates*. Rake seed in with the back of the rake. Spread ¼ -½” of good quality compost to help with establishment. Newly seeded areas should be kept moist until seed has germinated. Begin mowing when new seedling turf has reached 2”. After 3 or 4 mowings adjust your mower to the regular mowing height of 3”-4″.

You can call your local county Cooperative Extension Service to learn of the latest recommended pest-resistant varieties.

Adapted from:
Suffolk County Department of Economic Development and Planning
Division of Water Quality Improvement
H. Lee Dennison Bld., 4th Floor
100 Veterans Memorial Hwy
P.O. Box 6100
Hauppauge, NY 11788