With dry winds and intense sun, the soil dries out very quickly. All of your plants (including the lawn) will benefit from a slow soaking, about once a month.
When the temperature is above 40 degrees, bring out the hoses and turn them on. For each large shrub / tree water slowly for about 20 minutes; for perennials and lawn water an area for about 25-30 minutes.
This could be the factor between life and death for your plants during these dry times.
Shrubs
Newly planted shrubs require more water than established shrubs that have been planted for at least one year. The following recommendations assume shrubs are mulched to retain moisture. During the first growing season, a small sized shrub transplanted from a one-gallon container will require four to six gallons per week. Once established, small shrubs will grow well on two gallons per week. Larger shrubs may need as much as 10 gallons per week. True low water use shrubs may require less water than this.
In dry winters, all shrubs will benefit from winter watering from October through March. Apply five gallons two times per month for a newly planted shrub. Small established shrubs (less than three feet tall) should receive five gallons monthly. Large established shrubs (more than six feet) will require 18 gallons on a monthly basis. Decrease amounts to account for precipitation. Water within the dripline of the shrub and around the base.
Trees
Root systems can spread two to three times wider than the height of the tree. Most of the tree’s absorbing roots are in the top 12 inches of the soil. Water should be applied within the dripline. Water deeply and slowly, moistening the critical root zone to a depth of 12 inches. Methods for watering include a deep root fork or needle, soaker hose or by hand with a soft-spray wand.
As a general rule, apply ten gallons of water for each diameter inch of the tree. For example, a two-inch diameter tree will need twenty gallons per watering.
Fall and winter watering, October – March, one to two times per month, depending on weather, temperature and soil conditions.