It's tempting to adopt a "set it and forget it" approach to watering schedules based on the one-inch per week common advice. The truth is that water requirements can vary based on your location, soil type, wind exposure, sunlight, temperature, and plant composition. A better way to approach your watering schedule is to pay attention to the evapotranspiration rate for your location.
Evapotranspiration. or ET, is the water loss occurring from the processes of evaporation and transpiration. Evaporation occurs when water changes to vapor from soil or plant surfaces. Transpiration refers to the water lost through the leaves of plants. Understanding ET can help you water your plants more efficiently and take the guesswork out of sprinkler operation frequency and duration.
There are smart irrigation controllers and moisture meters that tie in with weather stations that can calibrate your sprinkler system. If you don't have one of those, you can still get the information from some great Texas A&M AgriLife Extension sites that provide calculators that tell you when to water.
The WaterMyYard website (https://watermyyard.org) lets you set up an individual profiles to receive watering recommendations for your type of irrigation system and local conditions. You can even receive their weekly watering recommendations by email and/or text messages. The program is in partnership with area sponsors or municipalities. Austin Water Utility does not participate, but you can still use the website by typing in the area that is closest to you. The primary areas served by this program are as follows:
- Cedar Park
- Cottonwood Shores
- Crystal Mountain
- Dripping Springs
- Hidden Valley
- Horseshoe Bay
- Lago Vista
- Marble Falls
- Point Venture
- Sandy Harbor
- Sunrise Beach Westlake Area
The WaterMyYard program is powered by the TexasETNetwork (http://TexasET.tamu.edu ), which has calculators to help you determine your watering schedule. There are nine LCRA weather stations (including the Austin Redbud location) with data and calculators to help you determine the amount and frequency of irrigation.
Use either of these resources to help set the right schedule for your individual yard. Since they are tied in with current weather data, you can be confident that you are not wasting water or letting things get too dry.