Irrigation is an artificial application of water to soil to enable satisfactory plant growth. It’s essential for successful gardening in the desert. The purpose of irrigating is to maintain soil moisture in much manner that normal root development and their vital function is facilitated and water is efficiently and conservatively utilized.
Irrigate the entire rooting zone
To maintain good growth, plants must root at least an extensively am they foliate. And feeder roots are generally most prolific under the outer 2/3 of their branch spread. Consequently, water should be applied under the entire foliage spread of trees, shrubs, etc.
Irrigate at the rate the soil will absorb it
Wasteful run-off can result if the water is applied too fast, and insufficient infiltration through root zones may occur if it’s applied too slow. Level ground and mulched surfaces facilitate water infiltration and retention.
Irrigate long enough to allow penetration through normal rooting depths
Grasses and flowers root at least a foot deep, established shrubs 2 to 3 feet, and most mature trees as much as 5 feet or more. It takes at least ½ hour for water to infiltrate the upper root of our average soils; 1 to 2 hours for 2 feet; 3 to 4 hours for 3 feet; and 6 to 8 hours to reach 4 to 5 foot depths. Dense silt and clay loam soils absorbs water slower but hold more and retain it much longer than the porous sandy or gravely loam. Remember, irrigate sufficiently each time – brief irrigation cause weak, shallow rooting and accumulate salts within root zones.
Irrigate no more frequently than necessary to sustan good growth
If you are attentive observer, the first signs of midday wilt on tender-foliage plants can be your clue to irrigate. But, symptoms may not be apparent early enough on some plants, or to novice gardeners. And prolonged dehydration of leaves worsens desiccation, the browning of their tips and edges. Frequent watering provokes limited rooting and increases wasteful evaporation loss. Excessive, deep watering excludes vital air from the soil and drowns roots.
Morning watering is best for plant health, sprinkler efficiency and water conservation. Appropriate adjust rate, duration and frequencies to minimize wasteful erosive runoff due to ground slopes, slow warming of spring and gradually decreased with the cooling of fall. Whenever changing irrigation practices, be attentive to plant response, particularly during hot weather and with older planting. To get seedlings and transplants started, keep soils moist, then, reduce frequencies and lengthen irrigation as roots establish.
Attentive supplemental irrigation is necessary in most landscapes. Although trees, shrubs, and flowers may be watered with lawn grass, they usually need longer watering to satisfy their deeper rooting needs. Trees especially, need occasional prolonged irrigation.
If evaporation cooler or swimming pool water is used for irrigation, make certain it doesn’t contain phytotoxic amounts of salts or other potential harmful chemicals. And only intermittent use can be safely recommended