Save water through Planning

Most of us have more water than we know what to do with. Even in and regions there are occasional deluges of rain. Rainbarrels are not a new idea, but still a useful one. Position clean, empty barrels beneath downspouts or up on blocks around the garden. Barrels, positioned a few inches above the ground, can incorporate spigots and drip tubing for a cheap, gravity-flow irrigation system. A barrel positioned high above the ground creates strong water pressure, and far-flowing water. This time-honored method is excellent for flower or vegetable gardens.

Lawns are water hogs. They also consume their share of fertilizer, mowing time, and expense. Compared to native landscaping or a xeriscaped yard they are a ludicrous luxury. (Xeriscaping is the landscaping art of combining drought-tolerant plants, garden design, and water-conserving tactics to create a low-maintenance landscape.)

Consider reducing water and other bills by creating a smaller lawn. You may even find that by enlisting the services of a paid professional landscaper, you could save buckets of money. Or try gradually replacing some of the grass with less thirsty landscape plants.

Be aware of which plants require the most water. Group them together so you don't waste water on plants that don't need it. Plants such as rhododendrons, azaleas, and ferns need more water than cacti. Also, if your yard has a naturally moist microclimate, put the water hogs there, not on the driest point of the property. Consider landscape points of interest that doesn't require water, such as a dry creek-bed of rock. Make it appear wet by varnishing the rocks. Position sprinklers to avoid watering sidewalks, streets, decks, and other structures; they won't grow.

Water Loss Means We All Lose

In a perfect world every drop of water you put on your plants would run straight to the roots and would be used immediately by the plant. But we have to deal with water loss. Knowing how to reduce it saves water and money.

Moisture is lost from the soil in several ways, but you can cut these losses. By incorporating lots of humus into the soil, you will lessen the amount of water that percolates through the soil and out of reach. Humus is a water magnet. A lot of water is also lost through evaporation from the soil surface. Thanks to capillary action through the soil, which draws water up from below, evaporation can deplete water from deep in the ground. Keeping the soil surface covered with mulch (see pages 109111) protects against this. Another line of defense against evaporation is to get less of the soil surface wet in the first place. This means replacing a sprinkler with a drip system, soaker hose, or individual water containers for landscape or large vegetable plants. Finally, transpiration, the way in which plants metabolize water, can steal amazing quantities of water from your soil. One large shade tree on a hot sum mer day can transpire several hundred gallons of water. Misting plants on hot, dry days helps limit the amount transpired and reduces plant stress.

As mentioned, air evaporation is also a major water waster if you use an overhead sprinkler. Water early in the morning or at night for the least water loss. If you want to keep your water bill down, never water during hot, windy weather.

How Much Water Is Just Right?

While there is no one answer to the question of how much water is just right for all gardens, there are some useful general guidelines. The most efficient and cost-effective way to water any plant is to fill the entire root zone with water, and let the soil become almost dry be fore the next watering. The amount of dryness depends on the plant. Let the top 2 or 3 inches dry out for most established plants. Let the soil around a large tree dry down several inches, but keep new or tiny plants moist to the top inch or so of soil.

Water most plants deeply and infrequently. When using a sprinkler, measure how many inches of water you apply by setting jars at intervals along sprinkler pathways. This will also tell you if the sprinkler gives even coverage.

Remember soil type affects how much water is necessary. Water sandy soils more frequently than clay soil. To make sure you are delivering enough water to where it is needed, use a soil probe or shovel before you water to determine the extent of dryness. Repeat the process after watering to see how deeply the water has penetrated into the soil.

Lawns. Use an overhead sprinkler. Water to a depth of at least 6 inches as soon as grass fails to spring up after walking on it. Avoid frequent, shallow waterings as they lead to shallow roots, which are far more susceptible to heat or drought. Aeration, or removal of soil plugs, helps send water to the root zone. Renting an aerator every other year or so also will help to reduce thatch build-up and combat compaction.

Vegetables, Bedding Plants, and Perennials. Water 6 to 12 inches deep every four to ten days for established plants. Don't wait for plants to wilt before the next watering. Wilting slows growth and reduces crop yields.

Soaker hoses or drip irrigation are efficient ways to water here. They can save up to 60 percent of the water used by a sprinkler. Place mulch over the hose to prevent evaporation.

A cheap version of drip irrigation is container watering. Bury a container, such as a plastic 1-gallon milk jug that has had 2 or 3 holes punched in the bottom, next to or between individual plants. Keep the containers filled with water and allow them to seep water directly into plant root zones. Tailor the size of the container to the size of the plant.

Sprinklers are not the best for vegetable gardens because they waste a vast amount of water. More water lands on the leaves, where it evaporates, than anywhere else. Hand watering is as much a waste of time as it is water. Unless you stand there for a few hours with a water wand, you cannot wet the soil deeply enough to do a worthwhile job.

Cultivate unmulched soil to increase water absorption. Crusted soil forms a barrier against water penetration.
Trees, Shrubs, and Landscape Plants. Water throughout the drip line of plants for the most efficient intake of water. Soaker hoses (see page 31) allow you to wind around individual plants. They are great for such shrubs as roses that are susceptible to moisture-loving disease organisms. Since no water rests on the leaves the diseases can't establish their spores. To allow water to slowly seep down into the soil, mound a ridge of soil around the outside of the drip line to form a basin and fill with water. Remove this soil during rainy weather to prevent waterlogged roots.

Plants on landscape berms. Check and water more frequently since they have more exposed soil from which water may evaporate.

New woody transplants. Water thoroughly both the nursery soil within the root ball and the native soil surrounding it. Failure to do so may prevent the roots from venturing into the surrounding soil, which can eventually kill the plant. Dead plants are an investment wasted.

Plants in containers. Water as soon as the surface feels dry. Keep a close eye on thirsty plants such as fuschias, which often need watering once or twice daily in hot, dry weather.