The last two years have been drought years with lower than normal rainfall amounts (the average annual rainfall in the Fresno/Clovis area is 11 inches). Water levels have lowered significantly in the underground aquifer that stores and supplies our drinking and irrigation water. So far this rainy season, snow and rainfall amounts are lagging behind normal. Water conservation efforts should begin now, just in case we are entering a third drought year.
As temperatures fall, monitor the soil moisture levels in all areas of your garden and adjust irrigations timers weekly. Our storms usually come in from the northwest or west. There may be rainy weeks when no additional watering is needed for lawns that receive rainfall directly, but areas that are sheltered from the rain (i.e., under tree canopies, on the leeward or rain shadow side of the house or other structures) might need a few minutes weekly of supplemental irrigation.
If we have a dry winter and spring, you'll need to make tough decisions about which plants to water. Ornamental lawns can be replaced fairly cheaply and easily but large mature landscape trees that shade homes and occupied buildings must be saved. Deep-soak landscape trees now and again in spring, keeping in mind that the roots extend about a foot deep and at least as wide as the canopy.
Amending soil to improve drainage and improve the soil's capacity to store water will help conserve water. Till compost or humus into planting beds, especially in areas where the soil has become compacted over time: Irrigation water runs off compacted soil and is wasted.
Mulches act as an insulation blanket, moderating temperature fluctuations and slowing evaporation.
A 3- to 4-inch layer of mulch also will prevent water-sucking weed seeds from germinating.
Replace overhead sprinklers with drip emitters and soaker hoses. Visit the Clovis Botanical Garden, which displays many types of water conserving irrigations methods as well as drought-tolerant plants suitable for our climate.
But don't rush to replace your English cottage garden with drought-tolerant native plants during a drought year.
Newly planted trees and bushes, including drought-tolerant varieties, need extra water for the first few years until their roots become established.
The Fresno County Master Gardeners offer classes on drip irrigation every year. Our demonstration garden, the Garden of the Sun, at Winery and McKinley avenues in Fresno, employs many water conservation methods and knowledgeable docents are always available.
Call 456-4151 for garden hours.