The Irrigation Association named July “Smart Irrigation Month” to promote, in their words … “efficient watering practices, technologically advanced irrigation products, and water conservation.”
In other words, let’s get smart about irrigation.
The Irrigation Association notes that most homeowners tend to overwater their landscapes or waste water through inefficient habits. The key to smart irrigation is applying just enough water, only when necessary, and in the proper place. To do this, there are five key things to check: placement, quantity, flow, filter and schedule.
Placement. Emitters, soaker hose, or plant wells need to be near the water absorbing (feeder) roots of the plants. Feeder roots extend far beyond the base of the plant in their search for water, leaving roots near the base of the stem for support.
Look at the green canopy of the plant. The edges of the canopy, where a light rainfall would drip off, are where the feeder roots are. A tree, shrub, or groundcover with a canopy five feet out from the stem or trunk needs a continuous circle of water placed five feet out from the stem or trunk. So check water delivery placement. You may need to move things around as plants mature.
Quantity of water depends on species of plant, season, amount and type of mulch, and soil type. The goal is for a single timer to deliver sufficient moisture to all plants on the system. For example, given two same-size bushes, rose and senna, the rose will need a greater quantity of water. You get this with either more emitters or a higher flow per emitter.
Change them out as needed. Yes, you can mix emitters on a single zone line.
Check for clogged or broken emitters. If they are clogged with calcium build-up, clean by soaking in vinegar. If soil has clogged the emitters, try blowing it out backwards. Soil shouldn’t be in a water system, so check for leaks in the irrigation system or holes in the in-line filter. Some emitters simply need replacement after several years exposure to the
Flow and pressure. Is the flow or pressure consistent throughout the system? Place buckets under emitters at the beginning, middle and end of your system. After 15 minutes, stop the flow and measure. Did the one gallon per hour emitter deliver a quart? You may need to use larger emitters at the tail end of your system to get adequate water to the plants there. Alternatively, there may be a leak. Look for damp spots or weeds that signify underground leaks.
Filter. Many of the newer irrigation systems have an in-line filter. It helps capture any solids that may be in the water as it comes into your system. Soil often gets into pipes because construction is a fact of life in Tucson. Clean the filter quarterly. If your system lacks one, they are easy to add.
Schedule. That dreaded gray box on the wall must now be dealt with. First, check for back-up batteries. Usually a 9-volt, it is best to replace these batteries once per year, especially before summer thundershowers cause power bumps that erase programs.
Control boxes vary in complexity and available settings. Check that yours knows the correct time and day of the week. Set it to deliver water just when plants need it — at dawn, when they “wake up” and start to photosynthesize. Avoid watering at night since plants can’t use water then, but fungal pathogens can. Besides, it merely evaporates if not used.
Depending on emitters, soil type, mulch, and plant species, the timer may need to be set to deliver as much as two to three hours of water two or three times per week in summer. One long, deep, watering is better than many shallow ones. Deeper water penetration encourages roots to grow deeper beneath the hot, drying surface of the soil. Guidelines say: three feet for trees, two feet for lawn and shrubs, and one foot for small perennials and annuals.
These five water-wise irrigation habits will result in a healthier landscape, conserve water, plus reduce your water bill. Now that’s smart!