Monday, September 22nd was officially the first day of fall—one of two days each year when the sun aligns with Earth’s celestial equator, and day and night are roughly equal, each lasting about 12 hours. This “equal night” is the equinox, and it happens again in spring, too. From here, the Northern Hemisphere tilts away from the sun, our days grow shorter and cooler, and the long summer light that drove growth begins to fade. That shift is why leaves change color: as trees transition toward dormancy, chlorophyll production slows, allowing the reds, oranges, and golds to show through. The date wiggles a bit year to year—thanks to calendar quirks and Earth’s not-perfectly-circular orbit, the fall equinox can land on the 22nd, 23rd, 24th, or 25th. Winter officially begins this year on Saturday, December 21.
Fun language note: before “fall,” English speakers said “autumn,” and before that, “harvest.” Americans mostly say ‘fall’; much of Europe sticks with ‘autumn’. Whatever you call it, the Season is a natural reset button—especially for irrigation and water management.
Why Fall Is Prime Time to Recalibrate Irrigation
Plants don’t need summer watering in a fall world. With fewer daylight hours and weaker, lower-angle sunlight, evapotranspiration (ET) drops—meaning the landscape loses less water each day. If your irrigation schedule doesn’t change, you’re overwatering: wasting money, inviting disease, and pushing roots shallow just when you want them deeper for winter resilience.
Here’s a practical, fall-savvy plan:
1) Dial Back Runtimes (Smartly)
Start by reducing total watering minutes by 20–40% from peak summer, depending on your climate and plant mix. If you have a smart controller, switch to seasonal adjust or ET mode and let it track weather shifts automatically. No smart controller? Use weekly forecasts and a simple rule: shorter days = shorter runtimes and/or fewer days per week. Prioritize deep, infrequent watering for trees and shrubs to encourage strong root systems.
2) Audit Your System When It’s Cool Out
Cooler mornings are perfect for an irrigation audit. Turn on each zone and look for:
3) Shift Spray to Drip Where It Makes Sense
Beds, shrubs, and trees love drip in fall. As canopies thin and winds pick up, spray loses efficiency; drip delivers water right to the root zone, reducing evaporation and overspray. If you’re not ready for a complete conversion, start with drip on new plantings and perimeter beds—easy wins that pay back quickly.
4) Mulch is Your Fall Superpower
Add 2–3 inches of organic mulch around trees and in beds (keep it a few inches off trunks). Mulch conserves soil moisture, buffers soil temperatures as nights cool, suppresses weeds, and builds soil health as it breaks down. It’s one of the most cost-effective, high-impact water strategies you can implement this Season.
5) Tune Overseeding and Turf Care to the Season
Suppose you overseed warm-season lawns with cool-season rye, water lightly and frequently only during germination (7–14 days). After establishment, taper to deeper, less frequent cycles. On established cool-season turf, use a cycle-and-soak method: split longer runtimes into two shorter cycles, separated by an hour, to prevent runoff on compacted soils.
6) Embrace the Weather: Rain and Freeze Protection
Install or re-enable rain sensors and freeze protection. Fall storms can deliver significant moisture; your system should automatically skip when Mother Nature pitches in. If you’re in a freeze-risk area, set your controller to inhibit irrigation when the temperature drops to 32°F to prevent icy walkways and plant damage.
7) Capture What the Sky Gives You
First fall storms are perfect for topping off a rain barrel or cistern and refreshing bioswales and infiltration basins. Direct downspouts into permeable areas where water can soak in slowly. Collected rain is chlorine-free and plant-friendly, and using it for hand-watering trees or containers stretches your budget and the watershed.
8) Prep for Winter—Don’t Procrastinate
In cold climates, schedule winterization (blowouts) before the first hard freeze; don’t gamble with buried lines and backflow preventers. In milder zones, you’ll still run irrigation in winter, just sparingly: often one deep cycle per week (or less) is plenty for established landscapes. Either way, protect exposed piping and backflows with insulated covers.
9) Set a Water Budget (and Track It)
Create a fall/winter water budget for each site or zone type (turf, shrub beds, trees). Many innovative platforms allow monthly budgets and will alert you if you exceed them. Even without innovative hardware, jot down meter readings or check your utility portal and aim to reduce your fall usage by 10–20% compared to last year through more intelligent scheduling, repairs, and mulching.
10) Communicate the “Why”
If you manage an HOA, campus, or parks system, post a short note: “Days are shorter, plants need less water, and we’re adjusting irrigation to match.” A little transparency reduces complaints and builds trust—especially when people see healthier plants and fewer puddles.
A Season of Color—and Conservation
Fall is often called harvest for good reason: it’s when we collect the benefits of good decisions made earlier in the year. But it’s also when small changes deliver outsized returns. A quick controller adjustment, a bit of mulch, a repaired leak, and a smarter watering rhythm can cut your bill, protect your landscape, and conserve a resource we all share. As leaves turn and the light softens, your irrigation should follow the Season—precise, restrained, and ready for winter.
Whether you say fall or autumn, let this equinox be your reminder: nature just flipped the switch. Now’s the moment to tune your system to match.
