It's sad but true: Homeowners waste roughly half of the water they use. Fully eight out of 10 homeowners water their lawns and gardens incorrectly, says master gardener Paul James, and those poor watering practices — besides wasting water — contribute to a large number of gardening problems, including poor plant growth, insect invasion and fungal diseases.
It's easy to prevent problems simply by changing your watering habits — from how you water, to when you water, to what you water when! Here are a couple of common mistakes we all make and solutions for avoiding them:
Mistake #1: Surface sprinkling. Watering every other day for 15 minutes at a time may be convenient for you, but it can be disastrous for your plants. Frequent shallow watering causes a plant's roots to grow near the soil surface, where they quickly dry out.
Solution: When you water, give your grass and plants a deep soaking, to a depth of 12 inches. This will encourage roots to penetrate into the subsoil, where the moisture level naturally remains more constant.
Tip: To prevent wilting, either from too much or too little watering, stick to a routine — for example, flower and vegetable gardens should be watered once a week, an hour at a time.
Mistake #2: Watering at the wrong time. The time of day you water is important. Watering in the evening isn't good because leaf surfaces usually remain wet overnight — an open invitation for fungal diseases. Midday watering is better for plants, but bad for your water bill because much of the water is lost through evaporation.
Solution: Try to water between 5 a.m. and 10 a.m., when the sun is low, winds are calm and temperatures are cool. Under these conditions, less water is wasted through evaporation and leaf surfaces have a chance to dry out during the day, reducing the chance of fungal diseases.
Tip: Water pressure from municipal water treatment facilities is typically higher in the morning, so it takes less time to deliver the same amount of water in the morning as it does during the day or night.
Watering trees and shrubs
As trees grow in size, they get thirstier. Young trees with a trunk diameter of two inches or less, for instance, need at least 10 gallons of slow-trickled water each week, whereas trees with diameters up to six inches require twice that amount. Thankfully, mature trees tolerate drought conditions better than young trees because of their extensive, fully-developed root systems, and the method for watering them is easy: just water your lawn regularly. Landscape shrubs should be watered every seven to 10 days (maybe five to seven days in summer), and be sure to deep-soak them, although it's okay for them to dry out a little between waterings. Moisture-loving rhododendrons and azaleas, however, need a constant supply of moisture and should not be allowed to dry out completely.
Tip: Reduce the risk of fungal diseases by watering the base of plants rather than the tops.
Generally speaking, grass lawns need about two inches of water each week. Simply turn on your sprinkler for an hour or two every seven to 10 days, depending on your climate. Remember, sandy soil drains quickly, so it needs to be watered often. Clay soil, on the other hand, holds water for a long time, so you don't need to water as frequently.
If you're watering on a slope or your soil is highly compacted, try watering in stages to achieve the best absorption. Water your lawn until you see runoff, then stop watering, wait until the runoff subsides and begin again.
Mulch, mulch, mulch
A great way to conserve water is to mulch your flower and vegetable beds. Mulch has multiple benefits besides water conservation: it suppresses weeds, stabilizes soil temperatures, adds organic matter and improves the look of your landscape. Cover the base of everything--trees, shrubs, flowers and vegetables--with a two- to four-inch layer of mulch.
What do you use? Some of the best organic mulches are pine needles, straw; wood chips made from pine, redwood, cypress or cedar; cocoa hulls; cottonseed hulls; and crushed pecan shells. Experiment a little till you find a favorite!