Preparing Your Irrigation System for Arizona Summer

Why Summer Prep is Critical in Phoenix

Arizona's summer heat is unforgiving. When temperatures climb above 110°F for weeks at a time, your irrigation system runs at maximum capacity—often 3-4 times daily for grass areas. Components that functioned adequately in spring fail under this extreme demand. A sprinkler head that misted slightly in March becomes a geyser wasting 10 gallons per minute in June. A controller with marginal programming creates brown patches that cost thousands to repair.

Summer preparation also dramatically impacts your water bill. Phoenix homeowners typically see water costs triple from April to July as irrigation demand skyrockets. A well-prepared system with optimized programming, efficient heads, and proper coverage can cut summer water use by 30-40% compared to a neglected system—saving $500-1,000 over the season while maintaining healthier landscapes.

Essential Summer Preparation Steps

1. Increase Watering Frequency and Duration

As temperatures climb from the 90s in April to 110+ in June, gradually increase both watering frequency and duration. Grass areas that needed 2-3 days per week in spring require daily watering (sometimes twice daily) once temperatures consistently exceed 105°F. Each zone should run 15-20 minutes for grass, 10-15 minutes for shrubs, and 30-45 minutes for trees with drip irrigation.

Don't make the common mistake of jumping from spring to summer schedules overnight. Increase watering gradually over 3-4 weeks as temperatures rise. This allows plant roots to adapt and prevents overwatering during cooler periods. Smart controllers handle this automatically by adjusting to daily weather conditions, but manual controllers require you to update schedules every 2-3 weeks from April through June.

2. Optimize Watering Times for Extreme Heat

Summer watering times are critical for water conservation and plant health. Water between 3-6 AM when temperatures are coolest (typically 80-90°F) and winds are calm. This timing minimizes evaporation loss—which can exceed 50% during midday watering in Phoenix's dry climate—and ensures water penetrates soil before the sun heats surfaces above 120°F.

For properties requiring twice-daily watering, add an evening cycle between 8-10 PM after sunset. Never water during peak heat hours (10 AM - 6 PM) as evaporation waste is extreme and water droplets on leaves can cause burn damage. If your controller doesn't support multiple start times per day, upgrade to a smart controller—the water savings pay for the upgrade within one season.

3. Inspect and Replace Worn Components

Summer's extreme demand exposes weaknesses in aging components. Inspect every sprinkler head for cracks, worn seals, and inconsistent spray patterns. Heads over 7-10 years old often have internal wear that causes misting, fogging, or reduced radius—wasting water and creating dry spots. Replace any questionable heads now before they fail completely during peak heat.

Check valve diaphragms for wear—valves that take 3-5 seconds to close or leak slightly when off will fail completely under summer's frequent cycling. Inspect all visible pipes for cracks or weak spots, especially PVC exposed to direct sunlight. UV exposure makes plastic brittle, and pipes that survived spring will crack under summer heat and pressure. Replace any compromised pipes before they burst and flood your property.

4. Upgrade to High-Efficiency Nozzles

Traditional spray heads waste 30-40% of water to evaporation and misting in Phoenix's summer heat. High-efficiency rotating nozzles (like MP Rotators or Precision nozzles) deliver water in larger droplets at slower rates, reducing evaporation to under 10% and improving soil penetration. They also provide better wind resistance—critical when afternoon monsoon winds gust to 30+ mph.

Converting to high-efficiency nozzles costs $3-5 per head but reduces water use by 25-35% while improving coverage uniformity. For a typical Phoenix home with 40-50 heads, the $150-250 investment pays for itself in one summer through reduced water bills. The upgrade also extends system life by reducing strain on pumps and valves from lower flow requirements.

5. Add or Expand Drip Irrigation

Drip irrigation is 90-95% efficient compared to 60-70% for sprinklers in summer heat. Convert shrub and tree zones from spray heads to drip lines wherever possible. Drip systems deliver water directly to root zones with minimal evaporation, and they're not affected by wind or heat. This is especially important for desert landscaping and mature trees that don't need overhead watering.

For existing drip zones, verify all emitters are flowing and add emitters to growing plants. Trees and shrubs that were adequately watered last summer have larger root systems this year and need additional emitters. Check that drip lines aren't exposed to direct sunlight—UV exposure degrades tubing and causes emitter failure. Bury exposed lines under 2-3 inches of mulch for protection and additional water conservation.

6. Verify Controller Programming and Backup

Summer storms and power surges can wipe controller programming. Before peak season, document your complete watering schedule—zone runtimes, start times, and seasonal adjustments. Take photos of controller settings or write them down. Replace controller backup batteries (typically 9V) even if they seem fine—batteries weaken in heat and a dead battery means losing all programming during a power outage.

Test your controller's rain delay and rain sensor functions. Summer monsoons bring intense but brief rainfall that should pause irrigation for 24-48 hours. A malfunctioning rain sensor wastes water and can drown plants during monsoon season. If your controller is over 10 years old, consider upgrading to a smart controller with cloud backup, weather-based scheduling, and remote monitoring—features that prevent programming loss and optimize water use automatically.

7. Clean and Flush the Entire System

Phoenix's hard water deposits minerals in pipes, valves, and emitters throughout the year. These deposits restrict flow and reduce efficiency, but they don't cause obvious problems until summer's high demand. Flush all zones thoroughly by removing end caps and running each zone for 2-3 minutes. This clears accumulated sediment before it clogs emitters or damages valves under summer's frequent cycling.

Clean sprinkler head filters and screens—even small debris reduces spray distance and creates dry spots. For drip systems, remove end caps and flush each zone until water runs clear. Consider installing inline filters on drip zones if your water has high sediment or mineral content. Clean filters prevent clogged emitters and extend system life significantly in Phoenix's challenging water conditions.

Summer-Specific Challenges in Phoenix

Expert Summer Prep Tips