Gardening : Raise Vegetables With Less Water
While there are drought-tolerant trees, shrubs, herbs and perennials, there are very few drought-tolerant vegetables. If you want to grow a vegetable garden in water-restricted areas of the Southland, you are going to have to sacrifice some of your water allotment from other areas of your landscape--such as your lawn.
But there are ways to conserve a great deal of water while providing adequate irrigation to your vegetable garden.
A home drip or trickle irrigation system will dramatically curtail water usage while it delivers the correct amount of water to your vegetables. This, of course, makes sense at any time, not just during a drought.
A good system will serve for a number of years and pay you back many times through its savings in time and water. Also, it makes it easy to water regularly, and regularity is what vegetables need for optimum growth.
Many of the home irrigation systems you find at nurseries and garden centers are small-scale versions of systems designed for the commercial grower. They use the drip or trickle method of applying water.
This not only conserves water, but has been found to speed plant growth and cut down weed growth. It is especially useful for gardens on slopes because there is practically no runoff.
The drip irrigation method originated in Israel and has been adopted here with good results. The concept is the release of a small but constant volume of water at regular intervals.
The water delivery system is composed of these elements: a device to reduce water pressure to the right level, a filter, some narrow plastic tubing and emitters that release water adjacent to the plant root zone.
The soil structure is not eroded, there is very little water lost by evaporation and the root zone is not flooded, which can be damaging.
Trickle irrigation is similar to the drip system, but water is released at a faster rate to avoid clogging the system. This eliminates need for a filter. Both systems are said to reduce water consumption by as much as 70% from what is used in flood irrigation or by sprinklers.
In addition to drip and trickle systems, soaker tubing is designed for small plants in rows, such as lettuce. The tubing is placed parallel to the row and close to the plants. It can be buried a couple of inches underground or it can run along the soil surface. Incidentally, the old-fashioned soaker hose does a fine job of distributing water on row crops at a slow, even rate if its volume is carefully monitored.
Recent arrivals on the water-thrifty irrigation scene are mini-sprinklers and drip tapes. The mini-sprinklers consist of small sprinkler heads designed to deliver water at a much slower rate than regular sprinklers; this eliminates water runoff.
Drip tape is a flattened tube that can be laid along rows of vegetables where it emits small amounts of water and prevents most evaporation.
In addition to irrigation systems, a water timer is a useful water-saving device. It is designed to measure the outflow of water and to automatically shut off when the desired gallonage has been delivered to the garden. It is of great benefit to those who forget to turn off the water. The saving in water alone will soon pay for the timer.
Water timers are available in different models ranging from inexpensive manual types to electronic models that can be programmed to accomplish a number of complicated functions.
Regardless of which water-thrifty irrigation devices you select, you should water your vegetable garden either in the early morning or in the late afternoon when evaporation will be minimal. Early morning is the best because it will minimize potential mildew problems.
Local nurseries and garden centers usually have a good selection of home drip or trickle irrigation kits. I have used the Drip Mist brand kits with good success. Mini-sprinklers and drip tape are newer items and may be more difficult to locate. Some nurseries will help you design a water-saving irrigation system to fit your particular garden and will supply you with the necessary materials.
