Cambrian: Opinion

Water-wise watering is better than no watering

Artichokes, shown here growing in the columnist’s garden, are one of the few vegetables that require little supplementary water.
Artichokes, shown here growing in the columnist’s garden, are one of the few vegetables that require little supplementary water. Special to The Cambrian

The question is: “How much water does my garden need?”

Gardeners seem to fall in two groups. There are those who over-water and those who under-water.

Over these past years of drought, we’ve had little choice but to under-water our gardens and landscapes. Now, in midsummer, they are looking dreadfully dry and parched. Even oaks that normally need no supplemental water are stressed.

Perhaps it’s time to re-evaluate garden water, however you are getting it, to get our plants through another loooooong summer season.

When I see a green, well-cared-for landscape, I assume someone is doing some kind of watering. Soaker hoses stretched around large shrubs can be effective. Hand watering, as in “standing with hose-in-hand and dousing the soil” is time-consuming, but water-wise.

Ordinarily, most plants need watering about once a week during the summer. Watering more often can cause root rot. Roots of plants in saturated soil die back from lack of oxygen. The dying roots decay. Root rot is especially common in heavy clay soil and happens most often when a pipe has leaked, God forbid! Root rot fungus already exists in native soil. This is one of the reasons not to use dirt from your garden in pots.

Under-watering is more common in Cambria for obvious reasons. Even with Mediterranean, Australian plants and succulents, the plant must have some water to survive.

During the first year, water young plants regularly, then you can slack off a bit. Roots do not grow at all in dry soil. The plant has no way of absorbing minerals and nutrients. They simply exist.

Before watering, break up the soil around plants, trees and shrubs to allow for proper soil penetration. The ends of tree roots are what take in the moisture you are providing, so it’s best to water at least 9 inches from the trunk and outward to the edges of the tree canopy where the root tips grow.

Think of the tree’s canopy as an umbrella. The roots that absorb water and minerals are at the outer edge of the umbrella where it sheds most of its moisture. Make a furrow at this point to hold in the water so that it does not “run away.”

Be sure you are keeping all bare ground covered with mulch. It will affect your water use more than any other conservation technique. Wood chips, bark chunks and pine needles are readily available. Fine mulches such as bark granules, wood shavings, cocoa shells and buckwheat hulls are attractive in perennial beds. Fine gravel or crushed stone look natural in rock gardens with succulents.

In the coming years, it appears that California — and much of the world — will need to continue the practice of “water-wise practices.” Compromise in order to manage the shortage of water. A little water is better than no water.

Lee Oliphant’s column appears the first and third Thursday of each month and is special to The Cambrian.

Tip of the month

Growing vegetables is a lovely hobby. Unfortunately, when done properly, vegetable plants require an inch of water per week. This converts about to 6 gallons per square yard per week. Yikes! Sandy soils should be watered twice per week, a half-inch each time. Clay or loam soils can receive their 1-inch requirement once per week.

Thoroughly soaking the soil with infrequent watering is always better than shallow watering. Deep soaking encourages plant roots to reach deep into the soil while shallow watering keeps roots close to the surface. Cover all dirt surfaces with 2 to 4 inches of mulch of your preference.