"Poa pratensis plant1" by Macleay Grass Man is licensed under CC BY 2.0.
Bluegrass is a variety of grass with over 570 species. Most varieties are common meadow grasses or forage for livestock. Typically a dark green grass with medium to high water requirements, Most species of bluegrass are considered high maintenance. The three species most important to lawn care professionals and homeowners are “midnight: Kentucky bluegrass, “Bella” bluegrass, and Kentucky bluegrass.
Kentucky Bluegrass is a dark green, sun-loving grass. Maintenance Intensive but very beautiful, Kentucky Bluegrass is a superb grass for high traffic areas due to its natural self-repair abilities. There are very high water requirements, so irrigation is typically required for the best results. Proper Fertilization is required, usually once a month or so for the best results. Turning a lustrous blue-green during the heat of the summer, Kentucky bluegrass is the most iconic cultivar of bluegrass. Forming a dense sod, typically used for homes, golf courses, and other locations where appearance is most important. For best results, mowing is typically recommended at 2-3 inches.
Another notable cultivar of bluegrass is “midnight” Kentucky bluegrass. Forming an even darker blue-green than typical Kentucky bluegrass, it demonstrates superior resistance to various fungal diseases such as dollar spot, leaf spot, and stem rust. Yet another cultivar of note is “Bella” bluegrass, developed by the University of Nebraska, growing only 2-5 inches high. Not as traffic or drought-tolerant as other grasses, this cultivar is unique in that it can be grown vegetatively from plugs instead of from seed, similar to warm-season grasses typically not grown in New England.
"Festuca rubra - red fescue" by Matt Lavin is licensed under CC BY-SA 2.0
Fescue is an extremely adaptable grass. Fescues tolerate a variety of adverse conditions such as drought, poor clay soils, and shade. Fescues can be grouped broadly into two main categories: course or fine fescues. Course fescues are typical of lawn grasses: wide blades, easily visible from a short distance. Fine fescues typically have thin blades and form a smoother, fuller sod.
Notable cultivars of fescue are KY-31, Creeping red fescue, and tall fescue. Ky-31 is a light green coarse fescue. Possessing a deep root system gives this cultivar excellent drought resistance. Ky-31 has superior heat resistance to most other grasses, significantly reducing the risk of browning during heat waves.
Creeping red fescue is a unique grass, typically identified by the very bottom of leaves near the ground being red. A wonderful low-maintenance grass. Creeping red fescue tolerates shade, poor soils low water, making this a great grass for homeowners looking for a hands-off lawn. Tall fescue is dark green grass. Typical of fescues it tolerates shade and drought well. Tall fescue typically grows from "tillers" - small roots which spread out via the base of the plant. This makes tall fescue easy to keep from spreading in garden beds but means reseeding is typically required bi-yearly as it has little to no self-repair ability.
Ryegrass is a very light green grass. An excellent low maintenance grass, similar to fescue, is Typically included in seed mixes as annual ryegrass to provide quick results. Unlike fescue, however, it does not spread via rhizomes or tillers and therefore has no self-repair ability. Annual ryegrass does not survive winters and so needs to be overseeded with another grass species. Annual ryegrass is only used to quickly establish a lawn. Followed by overseeding with a different grass variety, such as fescue or perennial ryegrass.
Perennial ryegrass is a very fine-bladed grass, usually, a core component of most commercial seed mixes due to fast germination and ease of establishment. Typically only tolerates light shade and light drought. One notable quality of perennial ryegrass is that it tolerates a low mowing height of 1-2 inches.
"Clover Lawn with Fescue grass."
Clover is not grass but a type of legume. Clover is typically thought of as a lawn weed. Clover assists lawns by providing key nutrients to grasses which enables healthy growth and full color. Featuring dark green leaves and greater drought tolerance than any other grass.
As a legume it fixes nitrogen into the soil, providing a key nutrient for grass growth. Typically overseeded onto an existing lawn or overseeded as part of a grass mix. One unique feature of clover is that it flowers from early spring to late summer. This can attract pollinators, which may be a problem around small children. This is typically solved by regular, weekly mowings.