The short answer: The seasonal adjust feature (also called water budget or percentage adjust) lets you increase or decrease all zone run times by a percentage without reprogramming each zone individually. If your zones are set to run 20 minutes each and you set seasonal adjust to 75%, each zone will now run 15 minutes. Set it to 125%, and they’ll run 25 minutes. This is the easiest way to adapt your watering to seasonal changes. In Oklahoma, you might run at 50-75% in spring and fall when temperatures are mild, 100-125% during July and August heat, and 0% during winter dormancy. It’s like a master volume control for your entire irrigation system.
How Seasonal Adjustment Actually Works
Think of seasonal adjust as a multiplier applied to all your programmed run times. Your original zone run times stay saved in the controller. The seasonal adjust percentage modifies how long zones actually run without changing the underlying program.
Here’s a practical example: You have four zones programmed for 15 minutes each (60 minutes total). At 100% seasonal adjustment, zones run their full 15 minutes. At 50%, each zone runs 7.5 minutes (30 minutes total). At 150%, each zone runs 22.5 minutes (90 minutes total). Your base programming stays the same. You’re just scaling up or down based on seasonal water needs.
This is much easier than manually adjusting each zone’s run time four times per year. One quick change to the seasonal adjust, and your entire system adapts.
Where to Find Seasonal Adjust on Your Controller
Rainbird controllers: Turn the dial to “Seasonal Adjust” or “Water Budget.” Use the + and – buttons to change the percentage. Some models show this as a percentage (75%, 100%, 125%); others show it as a scale.
Hunter controllers: Look for “Seasonal Adjustment” or a percentage symbol on the dial. Navigate to it and use arrow buttons to adjust up or down in 10% increments.
Orbit controllers: Often labeled “Water Budget” in the menu. Access through the programming buttons and adjust with +/- or arrow keys.
Smart controllers: WiFi-connected controllers often adjust automatically based on local weather data. You can also manually override through the app. Look for “Seasonal Adjust,” “Water Budget,” or similar settings.
Recommended Seasonal Adjust Settings for Oklahoma
Oklahoma’s climate varies dramatically throughout the year, and your irrigation should too. Here’s a general guideline based on typical Tulsa-area conditions:
March and April (spring green-up): 50-70%. Bermuda is coming out of dormancy. Temperatures are mild. Rainfall is often adequate. Light irrigation helps green-up, but grass doesn’t need full summer watering yet.
May and June (warming up): 75-100%. Temperatures are rising, grass is actively growing, and evaporation increases. Gradually increase watering as summer approaches.
July and August (peak heat): 100-125%. Oklahoma’s hottest months. High temperatures and dry conditions mean grass needs maximum irrigation. This is when your full watering program runs, possibly with a boost.
September and October (cooling down): 50-75%. Temperatures drop, days get shorter, and evaporation decreases. Bermuda slows growth as it prepares for dormancy. Fescue is more active in fall but still doesn’t need summer levels of water.
November through February (dormancy): 0-25%. Bermuda is dormant and doesn’t need regular irrigation. An occasional deep watering during dry winter periods can help, but your system should mostly be off. Consider winterizing your system instead of running it.
Common Seasonal Adjustment Mistakes
Setting it and forgetting it. The whole point of seasonal adjustment is to change it seasonally. If you set it to 100% in June and never touch it, you’re overwatering in fall and spring. Mark your calendar to review it quarterly.
Not knowing what it’s currently set to. Many homeowners have never looked at this setting. Check it now. You might find it’s been at 150% for years, wasting water and money.
Going too extreme. Jumping from 50% to 150% overnight can stress grass. Gradual changes (adjusting every few weeks as temperatures change) are better for lawn health.
Ignoring rainfall. Seasonal adjustment is based on typical conditions. If it rains heavily, manually pause your system or reduce the percentage regardless of what month it is. A rain sensor does this automatically.
Seasonal Adjust vs. Manually Changing Run Times
You could achieve the same result by manually changing each zone’s run time four times per year. But seasonal adjustment is faster and less error-prone. With seasonal adjust, you change one setting, and it applies to all zones proportionally. Manually adjusting means changing 6 or 8 or 12 zone times individually and then remembering what the original times were when you want to change back.
Another advantage: your base programming reflects the ideal run time for peak summer conditions. Seasonal adjustment simply scales that down for cooler months. You never lose your original settings.
Irrigation Services for Every Season
For more than 25 years, Complete Lawn Care has been helping Tulsa-area homeowners get the most from their irrigation systems. Proper seasonal adjustment is one of the simplest ways to improve lawn health and reduce water waste, but it’s often overlooked.
Our irrigation services include seasonal startup in spring, system inspections, controller programming, and winterization in fall. We can set your seasonal adjust appropriately and show you how to adjust it yourself throughout the year. If your system doesn’t have a seasonal adjust feature (some very old controllers don’t), we can recommend upgrade options.
The Bottom Line
Seasonal adjust is a percentage multiplier that changes all zone run times at once.
Adjust it quarterly to match Oklahoma’s seasonal water needs.
50-75% for spring/fall, 100-125% for summer, and near 0% for winter dormancy.
Check what yours is set to right now. It might be wasting water without you knowing.
Want Your Irrigation Professionally Optimized?
Complete Lawn Care offers irrigation inspections and seasonal tune-ups throughout the Tulsa metro. We’ll check your coverage, adjust your programming for the current season, and make sure your system is running efficiently.
Phone: (918) 605-4646
Email: [email protected]
Online: completelawncaretulsa.com/get-a-quote
Proudly serving Tulsa, Broken Arrow, Owasso, Jenks, Bixby, Sand Springs, and surrounding Oklahoma communities since 2000.