by Diane Sagers
CORRESPONDENT
Summertime is when everyone finds good uses for water. We like to splash around in swimming pools, float down rivers, boat around on lakes or stand on the shore and pull out a few fish. We gravitate toward water areas.
Plants also make extra use of water during the hot summer season. About half the water used by most households goes toward watering plants and landscapes. In our desert climate that isn't much of a surprise. Since the water doesn't flow freely from the skies, we must add from our groundwater supplies.
That is a given. We must add water to support plants in our desert climate. Ironically, in this dry climate, more plants die from excess water than from drought. Properly applied, a lawn and most garden plants can grow through the spring, summer and fall months on about 36 inches of water. Most landscapes are given at least twice that amount or more.
We can have beautiful landscapes without nearly the amount of water that most people apply. There are many tricks to reducing water use without jeopardizing the health of our plants. Deep-rooted plants hold up better in hot, dry weather than those with shallow roots. Watering a bit every day may keep plants looking good as long as you are there to add the water. Given a very hot spell or a time when you must be away for a few days, the plants will quickly suffer. Water appropriately and the plants will develop deep roots.
In very hot, dry weather and long days, lawns require 2 to 2 1/2 inches of water during the course of a week. If your average water output in 30 minutes is say half an inch, you can run it for an hour to put 1 inch of water on your grass or gardens. Later in the week, you run it for another hour and you have given the plants 2 inches of water.
One way to find out just how much water your plants are getting is to measure the water output of your sprinklers. Put a series of tall cans (six to 10) in various spots at different distances around your sprinklers. Turn on the water for 30 minutes. Measure the water in each of the cans you put out and add those amounts together. Divide by the number of cans to get the average water output in 30 minutes.
Water must be in the root zone to do any good, and it must penetrate deeply so that the roots will grow down to find it. Check to see how deep the water you are applying is penetrating into the soil. Push a long screwdriver into the newly watered soil until it meets resistance. Hold the spot at the top of the ground and pull out the screwdriver. The length of the blade that was in the ground is the depth of penetration.
Grass roots do not extend more than 6 to 8 inches into the soil. If the water is seeping 12 inches deep, 4 inches of that is wasted.
Different types of soil require different irrigation methods to get the water to the right depth. Plants grown in clay soil or sandy soil still require only about 2 inches of water each week, but how it is distributed affects how that water should be applied.
Clay soil holds water for a long period of time, but a given quantity of water doesn't soak as deeply or as quickly as it would in sandy soil. On the other hand, water soaks deep and drains away quickly in sandy soils.
You might apply 1 1/4 inches of water to clay soil twice a week or a little more every five or six days so it will soak deeply enough. The soil will hold the water until the next watering.
In sandy soil, all that water will drain away and the plants will need water again sooner. In that case you might choose to water half an inch or some similar amount every other day. It is important for the water to soak down about six to eight inches to help the roots of the plants grow deep.
Sometimes you can apply water to lawns and it will not soak in very well because of the thatch layer at the soil surface. Thatch should be about half-inch thick -- no more. Aerate your lawns at least once or twice a year to keep the thatch layer at a healthy thickness. The air that gets into the soil will help your plants develop better roots, allow water penetration, and help keep the thatch at the right thickness.
If you have dry patches in your lawn, first check your sprinkling system. Often we set systems to water at night and we do not see plugged heads.
When you water a lawn, you want the water to best be used at the best time. During the hot part of the day, a good portion of sprinkler water evaporates before it hits the ground. Water during the cool hours of the day. Consider drip irrigation systems for garden areas. These put the water on the ground right around the plants. No water is wasted on weeds, between desirable plants and it does not evaporate before it gets to the soil.
The following tips from the Jordan Valley Water Conservancy District will further help save water in our landscapes.
Outdoor
No outside watering between the hours of 10 a.m. and 6 p.m.
Repair all broken, leaky, or malfunctioning sprinkler heads, pipes, and valves.
Adjust misaligned sprinkler heads to water landscaped areas only.
Adjust sprinkler heads and watering times to avoid run-off. For example, rather than running each zone of your sprinkler system for 30 minutes, consider running each zone for 10 minutes in three consecutive cycles.
Minimize spray washing of sidewalks, driveways, parking areas, or other paved surfaces.
Wait until the weather warms and dries substantially to set automatic sprinkler clocks. Water manually only when needed during early season months.
Turn sprinklers off following a rainstorm. Discontinue watering until landscaped areas are in need of water.
Discontinue watering non-essential areas.
Adjust sprinkler schedule according to the season.
Hand water dry spots.
Consider zonal design for your sprinkler system that apply water at different rates according to the water requirements of the areas you are watering. For example, trees and shrubs may have different watering requirements than turf grasses.
Indoor
Check all faucets, pipes and toilets periodically for leaks.
Install water-saving shower heads.
Replace your current toilet with a low-flow toilet or place a brick in the tank.
Take shorter showers or take a bath.
Turn off the water while shaving or brushing teeth, etc.
Run your dishwasher only when full.
Select proper water level for laundry.