When it comes to manicured lawns, the green choice is always to go without unless the lawn is functional and practical for, say, a play area for kids. Otherwise, lawns use a ton of water, and don't offer many benefits. How much water does a lawn require to stay green? It depends on the size of your lawn, but according to the Handbook of Water Use and Conservation, the average lawn uses an estimated 10,000 gallons of water per year, not including rainwater.
Nevertheless, the idea of the lawn is too well-ingrained in the American psyche for it go away anytime soon. With that in mind, are there ways to have one's cake and eat it too, or in other words, to have a waterless lawn?
The Grass is Greener
The zero-water lawn does exist with synthetic grass, the modern offspring of AstroTurf. I have seen a front yard completely redone with this product and I must say, it actually looks like real grass until you get within a couple feet. If you love the look of a manicured lawn and water consumption and labor are your main concerns, this might be the option for you. It is perennially lush green, it feels good underfoot, it is soft and matches yard contours, and never needs to be mowed or watered. Companies like SynLawn are producing it.
While you're saving water and labor, there are environmental drawbacks. To start with, synthetic lawns are made from a non-renewable, petroleum-based source that will one day wear down and end up in a dump. Also, I noticed that weeds tend to grow at the borders of the turf, which looks strange. Also, you're basically covering up your yard with a plastic sheet... I would personally take a drought-tolerant native plant garden into consideration before going with synthetic lawn.
Going Green -- Naturally
If plastic grass is an option you're not willing to consider but your goal is still a zero-water lawn, you're out of luck. Sure, you don't have to water your lawn, and some varieties of grass require much less water than others (see below), but part of the natural cycle of grass in nature is to produce seed and then dry out and wait for the next rainy season. That means if you never water your lawn, it will not stay green on its own. However, the following are some options which require the least amount of water. DIY Resource: http://www.networx.com/article/landscaping-the-waterless-lawn
Bermudagrass, originally from Africa, is an excellent example. Not only can it survive drought conditions and high heat, but also poor soil and foot traffic because of its coarser stems and leaves and deeper roots than other grasses. However, because it spreads by rhizomes and stolons, bermudagrass spreads vigorously and can build up excessive thatch which can lead to further problems. For all its good qualities, bermudagrass does not handle shade or cold well and will die in climates with serious winters.
Another drought-tolerant grass is zoysiagrass, originally from Southeast Asia. It spreads much slower than bermudagrass and performs better in shade. However, it has rather stiff leaves that aren't comfortable to walk on and starts to look brown earlier in the fall and continues later in the spring than other grasses. DIY Resource: http://www.hometalk.com
Like other native plants, regional native grasses are adapted to local conditions, which includes local hydrological conditions. This is good news if you're looking for a grass that needs less watering on your part... Afterall, nobody was watering them in nature and they did just fine. The only "problem" is that in the natural course of things, un-managed grass does not stay green and short all year round. For that, some amount of watering and mowing is necessary.
If you're interested in a native lawn, you'll have to do research in your area. One example is buffalograss, native to the prairies of North America (it was a food supply for buffalo). It is drought- and heat-resistant and used as a turf grass.
Another variety is red fescue, native to California. Left to its own devices, it will take on a pleasant meadow look.