Increasing water-use efficiency

Mulching:  Mulching can increase water infiltration rates, decrease soil temperatures, decrease evaporation, and reduce weed growth.  Trials have shown that mulching can reduce irrigation requirements up to 25%.

Infrequent Watering: Maximize the length of time between irrigations.  This decreases water loss to evaporation.

Drip Irrigation:  Drip systems decrease the amount of water lost to evaporation.  Keep in mind that root development is where the water is – drip irrigation does not wet a large portion of the soil and may inhibit tree growth if not designed properly.  Many growers in the valley have to supplement drip with overhead cooling.  Frequent, short bursts of water from overhead sprinklers result in very high evaporative water loss.

Irrigation Timing:  Irrigate at night and early in the morning – the cooler temperatures reduce evaporation.  Sprays are more effective when applied to dry trees.