When Is the Best Time to Turn On Your Irrigation System in Colorado?

If you’re a homeowner in Westminster, Northglenn, Thornton, or the surrounding Front Range, knowing when to turn on your irrigation system is key to protecting your investment and keeping your lawn healthy. Turning it on too early can lead to freeze damage, while waiting too long can stress your turf and plants. Here’s everything you need to know—plus what to look for and the most common irrigation repairs we see each spring.

Best Time to Turn On Your Irrigation System

In Colorado, the ideal time to turn on your sprinkler system is typically mid-April to early May, depending on weather conditions.

What to watch for:

• Overnight temperatures consistently above 32°F

• Soil is thawed and no longer frozen

• Extended forecast shows no hard freezes

• Local watering restrictions allow system operation

For areas like Westminster and Thornton, late April is usually the sweet spot. Higher elevations or shaded properties may need to wait a bit longer.

👉 Pro tip: A late spring freeze can still happen. Turning the system on gradually and keeping the main shutoff accessible can save you from costly damage.

What to Check During an Irrigation Startup

Before running your system at full pressure, a proper inspection is critical. Here’s what you (or a professional) should look for:

1. Main Line & Backflow Preventer

• Check for cracks or leaks caused by winter freezing

• Ensure the backflow device is intact and upright

• Look for water pooling near the foundation or valve box

2. Valves & Zone Operation

• Turn on zones one at a time

• Listen for hissing or bubbling, which may indicate leaks

• Make sure each zone turns on and off correctly

3. Sprinkler Heads

• Broken, sunken, or tilted heads

• Heads spraying sidewalks, fences, or siding

• Uneven spray patterns or low pressure

4. Controller & Programming

• Update schedules for spring watering

• Adjust run times for cooler temperatures and spring rainfall

• Confirm the controller communicates with all zones

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Common Irrigation Repairs We See in Spring

After winter, irrigation systems often need small repairs before they’re fully reliable. The most common issues we handle in Westminster, Northglenn, and Thornton include:

✔ Broken or Cracked Sprinkler Heads

Often caused by freeze expansion or lawn equipment.

✔ Split PVC or Poly Lines

Freeze damage underground can cause leaks that only appear once the system is pressurized.

✔ Faulty Valves or Solenoids

Zones that won’t turn on—or won’t shut off—usually point to valve issues.

✔ Leaking Backflow Preventers

A very common spring repair that, if ignored, can lead to water waste and code violations.

✔ Wiring or Controller Issues

Rodents, moisture, or corrosion can prevent zones from running properly.

Why a Professional Irrigation Startup Is Worth It

A professional irrigation startup ensures:

• Early detection of hidden leaks

• Proper pressure testing

• Efficient water use

• Protection of your lawn, plants, and foundation

It also helps you avoid wasted water, high utility bills, and emergency repairs once peak watering season hits.

Schedule Your Irrigation Startup in Westminster & Surrounding Areas

If you’re in Westminster, Thornton, Northglenn, or nearby Colorado communities, our team at K&G Landscaping & Hardscaping offers professional irrigation startups, inspections, and repairs to get your system running safely and efficiently.

📞 Call or text: 720-546-3102

📧 Email: contact@kglandscaping.biz

🌐 Visit: www.kglandscaping.biz

Don’t wait until a dry patch—or a flooded yard—tells you something’s wrong. Get your irrigation system ready the right way and enjoy a healthy, green landscape all season long 🌱💧