Water Water Everywhere

By Shirley Barker Special to the Planet
Thursday July 24, 2008 - 10:02:00 AM

Water rationing strikes terror into the heart of the gardener. How on earth can one conserve water and maintain healthy plants? 

Recently I bumped into a gardening acquaintance who urged me to address this imminent problem. “Tell us what we should do!” she wailed. “I don’t know!” I wailed back.  

She went on to say that in spite of her underground irrigation system, installed at great expense, her plants were dying. Clearly there was a leak. She had it fixed eventually, at a cost of time, money, water and plants. 

As I listened to this story I realized I did have something to say. First of all, gardeners routinely tend to overwater. Watering is one of those things that tweaks our conscience. Like a religious ritual, it has to be done right or something awful will happen. So we overdo it, for safety. If it costs a lot, so much the better will we feel. 

Experts reinforce this by telling us that long, deep watering is crucial to plants’ health, regardless of the size of their roots. 

The truth is that many shrubs and trees will come through a hot dry summer with no ill effects and no water, even fuchsias if the water table is high. Mulching helps to minimize surface evaporation, retain moisture and regulate soil temperature. 

Secondly, irrigation systems of all kinds are expensive to install, fiddly to maintain, and constant in their capacity to break down. Unless one is farming acres, irrigation systems are a waste of time, money and water. Underground systems are particularly heinous. How can one tell if individual plants are having their water needs met in appropriate amounts?  

As for systems that are computer operated, computers can not tap a barometer, watch a weather forecast, or look up the National Weather Service, all of which help the human gardener to decide when and how much to water. 

One even sees automatic sprinkler systems operating during the rainy season. Municipal groundsmen are as guilty of allowing this as are private property owners. 

Irrigation systems often spurt water at the leaves of plants. Many plants are vulnerable to water-borne diseases, mold, mildew, viruses and blight. Their leaves should never be watered, just the roots. 

Irrigation systems love to water sidewalks. 

Are soaker hoses a solution? These lie on the ground curving around plants, attached to a regular hose at one end. The gardener turns on the tap at the other end of the hose and goes indoors for breakfast. Are we approaching the root of the problem here? Are we seeking quick solutions at the expense of common sense and a little energy? Soaker hoses can fail to deliver just as devastatingly as other irrigation systems. One authority gives them one year before they clog. I can confirm that, in my raspberry patch. Leaves turned crisp and brown in spite of what I wrongly assumed was soaking. 

There is one solution that is foolproof, and it will separate the dedicated gardener from the ornamentalist who would rather go to the gym than get down and dirty with a shovel. That solution is to hold the regular hose and direct the flow of water by hand, making sure it is going exactly where it is needed, neither too little nor too much. A soft mulch of organic materials (never newspaper or plastic) will help to retain water around vegetables as well as shrubs. If a sapling fruit tree needs water for its first two summers, the hose can be left to run for five minutes or so about a foot or two from the trunk, and then moved until all four main points of the compass have received the same amount. Test the soil a week later. If it is still moist 8-12 inches down, it does not yet need more. 

We all want our gardens to be lush and beautiful, but Berkeley isn’t the tropics. Every summer is drought time in this climate. And if we lose some ornamentals to genuine drought, we can replant with natives that have adapted to no summer rain. 

Sooner or later the rains will return, and someone will wail, what can one do about garden floods? I don’t know….