Watering 101
The greatest waste of water is watering too much, too often. Here in the Portland metro area, summer water use often doubles or triples due to outdoor watering.
The reason for this is often because people don’t know how much water their landscape needs. And, it’s one reason why irrigation — whether it’s a single sprinkler attached to a hose or a sophisticated underground system — is a key component to your water conservation efforts.
Below are some basic irrigation tips to get you started. For more in-depth information check out the rest of our irrigation section.
- Water When Temperatures Are Cooler and the Air is Calmer
Make sure you water before 10 a.m. or after 6 p.m. when temperatures are cooler and the afternoon winds have calmed so that evaporation is kept to a minimum.
- Group Plants With Similar Water Needs
- Know How Much To Water
On average, we recommend watering your lawn about an inch a week – a bit more during long, hot, dry spells and a bit less during the cooler spring and fall. Trees, shrubs and perennials typically don’t need water as frequently, however they may require more volume at each cycle, so it is best to check with your local garden center or landscape professional on your plant’s specific watering needs.
- Apply the Amount of Water Your Soil Can Absorb
Watering thoroughly, but infrequently, will help roots go deeper, resulting in more water-efficient, drought-tolerant plants. This is one reason the Consortium recommends watering one or two times per week.
But, the amount you water should be based on your landscape’s soil conditions and plant needs. Here in the Pacific Northwest, soils are typically clay or sandy loam which may take longer for the water to penetrate. Run off and puddling are visible cues that water is being applied at a quicker rate than it can be absorbed.
If this occurs, you may want to use a “cycle and soak” pattern for your watering. To do this, apply water in several shorter sessions each day that you water. This will allow the water to soak gradually into the soil in between the watering sessions and allow for better water absorption and to prevent run-off.
For example, if your watering schedule is 40 minutes per week and you plan to water two days per week, your new “cycle & soak” schedule might be to water for 10 minutes at 6 a.m. and then again for 10 minutes at 8 a.m. each day that you water.
- Set It, But Don't Forget It
The key to efficient irrigation is to adjust watering schedules frequently during the irrigation season. If you set your automatic controller once for the hottest part of the summer and let it run all season, you will waste a lot of water. Most modern controllers allow you to easily adjust your watering schedule based on the weather.
