A proper irrigation schedule keeps your lawn healthy and protects your system from damage. This St. Louis irrigation calendar explains when to perform spring irrigation startup, make seasonal adjustments, and complete irrigation winterization. Following this timeline helps you avoid repairs and keep your sprinkler system running efficiently year-round.
When To Turn On Your Sprinkler System
Spring sprinkler startup should begin after the last freeze in St. Louis, usually between mid-March and late April, depending on weather conditions. Starting too early can damage pipes and system components, so timing matters. Once temperatures stay above freezing, turn the system on slowly and check for issues to set the foundation for the season.
Spring Startup Checklist:
- Turn on the water supply slowly
- Inspect sprinkler heads for damage
- Test each zone for coverage
- Check for leaks in valves and lines
- Set your controller for spring watering
Spring Irrigation Startup (March to April)
Spring irrigation startup is when your system comes back to life after winter and needs a full inspection to restore proper function. Skipping this step can lead to leaks, poor coverage, and wasted water early in the season. Start with light watering and increase gradually as temperatures rise, aiming for about 1 inch of water per week, including rainfall.
Key Adjustments To Make:
- Begin with 1 watering per week
- Increase frequency as temperatures rise
- Adjust zones based on sun exposure
- Monitor soil moisture levels
Mid-Season Tune-Up (June to August)
A mid-season tune-up keeps your system efficient during peak summer heat when water demand is highest. Small issues, such as misaligned heads or pressure problems, can quickly become costly repairs if ignored. Regular adjustments help maintain coverage, reduce waste, and keep your lawn healthy through the hottest months.
Mid-Season Tune-Up Includes:
- Adjust sprinkler head alignment
- Check water pressure and flow
- Fix dry spots and overspray
- Inspect for hidden leaks
- Update watering schedule
Summer Watering Guidelines
Summer watering should be consistent but controlled to support strong root growth and avoid stress. Most St. Louis lawns need watering 2 to 3 times per week, depending on heat and rainfall. The goal is deep watering at the right time of day to improve efficiency and prevent disease.
Best Practices For Summer Irrigation:
- Water early in the morning
- Avoid watering at night
- Water deeply, not frequently
- Adjust based on rainfall
- Watch for signs of overwatering
When To Winterize Sprinklers
Irrigation winterization should happen before the first hard freeze in St. Louis, typically between early October and early November. Waiting too long can leave water in your system, which can freeze and cause cracks or major damage. Proper timing protects your irrigation system and prevents expensive repairs.
Fall Sprinkler Blowout (October to November)
A fall sprinkler blowout removes all water from your system to prevent freezing and cracking inside pipes and valves. This is one of the most important maintenance steps of the year and protects your system from costly winter damage. After irrigation winterization is complete, your system stays off until spring.
Quick St. Louis Irrigation Calendar
| Season | What To Do |
| Spring (Mar–Apr) | Spring irrigation startup, system inspection |
| Early Summer (May–Jun) | Increase watering, adjust zones |
| Peak Summer (Jul–Aug) | Mid-season tune-up, monitor performance |
| Fall (Sep–Nov) | Reduce watering, irrigation winterization, sprinkler blowout |
| Winter (Dec–Feb) | System off, plan repairs or upgrades |
Stay On Track with Pro Outdoor
Keeping up with your irrigation schedule can be time-consuming without the right experience. Pro Outdoor provides spring sprinkler startup, mid-season tune-ups, and irrigation winterization in the St. Louis area. Contact us today to keep your system running properly all year.