Tips for Saving Water: Lawn water conservation
Wise use of water in your garden and lawn helps protect the environment and saves you money too.
Choose the Right Plants
Simple ways of reducing the amount of water used for irrigation include growing plants that are adapted to dry conditions, mulching, adding water retaining organic matter to the soil, watering early in the morning, and installing windbreaks and fences to slow winds and reduce evaporation.
Water is necessary for photosynthesis, the process by which plants manufacture their own food from carbon dioxide and water in the presence of light. The lack of water, nutrients, temperature, and amount of light can limit the growth of a plant. Too much water on plants can lead to excessive growth and fungal diseases and increases the risk of fertilizer and pesticide run-off from the lawn to paved surfaces.
Most lawns need only one inch of water per week, either from sprinklers or rainfall. This can be accomplished with deep and frequent waterings, which maintain a healthy root system and reduce weed infestation. Light and frequent irrigation promotes shallow roots and germination of weed seeds. An inch of water can be measured by marking the side of a tuna or pet food can placed on the lawn. Remember that irrigation is not needed following an inch of rainfall. One inch of water on a 1,000 square foot yard equals about 625 gallons.
Watering early in the morning, between 4:00 a.m. and 8:00 a.m., or at night minimizes water loss to evaporation. Drip irrigation or soaker hoses can reduce evaporation losses 20-50 percent and are excellent ways to apply water where it is needed, by avoiding watering sidewalk, streets, or causing runoff.
Water does not easily penetrate clay soils and water passes too quickly beyond the root zone of plants in sandy soil. Adding organic matter such as compost to clay and sandy soils will increase the penetrability of clay soils and the water holding capacity of sandy soils.
As plants grow and become more established, they often need less water. Newly sodded or seeded lawns require more frequent watering for the first 3-4 weeks. Applying small amounts of water several times weekly is detrimental to the grass and actually promotes a lawn that requires more water and one that cannot withstand drought stress. Less frequent, longer irrigations will help to promote a deeper, more viable root system. Lawns should only be watered when the first signs of wilt occur. Spots in the lawn that turn bluish-gray, footprints that remain in the grass long after being made, and many leaf blades folded in half length-wise are all indications that the lawn needs water.
When the weather and seasons change, adjust your watering schedule. On warm or windy days, plants and soils dry out more quickly. During cooler and wetter months, you will not need to water as often. Check the soil periodically for moisture content.
Trees and shrubs are most vulnerable in the first five years of planting and require more water than in subsequent years when they are usually more drought tolerant. Mulch on the soil surface cuts down on water loss due to evaporation and discourages weed growth. Use landscape fabric between the soil and your mulch to further reduce the likelihood of the weeds returning. A two-inch layer of mulch or compost is recommended. Apply mulches to shrubs, trees, annuals, vegetable gardens, and even containers.
An often overlooked practice in maintaining a healthy lawn is mowing. Infrequently mowed lawns are more prone to stress, resulting in thinner turf and a weaker root system. The first key is to keep the blade sharp. A dull blade rips instead of cuts leaving a ragged edge that loses more water. Mow the lawn at the highest setting proper for your type of grass. Removing more than 1/3 of the length of the grass blade per cutting places the grass under stress, reducing its ability to manufacture food to sustain growth. Adjust your mowing frequency to keep pace with the growth of the lawn. In the summer you might need to mow more than once a week. In the cooler spring and fall, mowing will be less frequent. When you mow frequently, clippings should be returned to the lawn to return nutrients and organic matter back to the soil.