Summary: Watering the lawn the why, how and when on the best practices of watering the yard and grass. Discover the principles of lawn watering which are actually very simple.
Question: In watering the lawn what are the best watering practices and rules we should follow for efficient, thorough watering of our lawn. I know why we water the lawn but how long, when and in what quantities should we water? Thank You Tim, Dale City, Virginia
Answer: Tim, in lawn watering there are some important factors to consider. Way to often homeowners think watering the grass often is the best water practice. However, that is not true.
Despite the widely held and much enjoyed belief to the contrary, the secret of luxuriant lawns of healthy grass is not necessarily lots of water… certainly NOT quantities of water sprinkled with happy, short-lived abandon whenever the mood hits the hose-happy gardener.
Indeed, the best watering practice for your particular lawn may well be not to water, but to exercise noble restraint; for many grasses, except in arid regions, require no watering at all.
But let’s begin at the beginning. The principles of watering lawns are actually very simple. First we’ll consider the “how” (and “why”) and then the “when.”
Most Ignored Fundamental Watering Lawn Rule
One of the most fundamental rules and perhaps the one most often ignored… is to apply water no faster to your grass than the soil will absorb it. Light sandy soil may take as much as 3 inches an hour, but this is highly unusual.
Average soils absorb little more than one-half inch (perhaps 1 inch) an hour, and very few sprinklers can deliver that small an amount.
The result is wasteful runoff and puddling. And if, as so often happens, people misinterpret the flooding as evidence the lawn has had enough and shut off the sprinkler, shallow watering is an additional – and extremely harmful – result.
Single Success Factor In Lawn Irrigation
Above all, when you do water the lawn, water thoroughly—all the way down to where the grass roots ought to be, 6 or 7 inches below the surface. Shallow watering is worse than no watering at all, for it encourages the roots to seek moisture near the surface.
The result is disaster when sprinkling is discontinued for even a few days or when an exceptionally hot spell occurs to dry and literally bake the roots. Thorough deep-down watering is perhaps the most important single success factor in lawn irrigation.
How Often Should You Water the Lawn
How often should you water? Some very excellent studies indicate that lawns should be watered “only when needed” – that is, you should always wait until the grass begins to wilt slightly before watering it.
And, with the exception of creeping bent grasses, which require pretty constant watering, the greater the interval between soakings, the better the grass stand is likely to be.
At Davis, California, an arid region where in summer no rain falls for some six months straight and daily temperatures average 100°, where tests indicate that common bluegrass can go 24 days before it begins to wilt and needs watering.
Merion bluegrass, an improved Kentucky bluegrass, can go 36 days before starting to wilt, considerably longer than the unimproved form. In some test, researchers found some Bermuda grass roots went down 6 feet.
Indeed, in all but very arid regions, properly fertilized Bermuda grass, and even more particularly zoysia grass, provides nearly perfect lawn with no watering at all. (Adequately fertilized lawns, incidentally, always require less water.)
Furthermore, tests indicate that even better than zoysia alone is the combination of zoysia and Merion bluegrass.
With diminishing supplies of water for domestic use a not-too-distant likelihood, the future trend will probably be to select the most drought-resistant grasses obtainable and provide them with the most adequate fertilizing program possible. The net result should be greater lawn satisfaction with less watering than ever before.