Winter Watering Schedule for Glendale Yards and Frost
A winter watering schedule for Glendale: when to cut back after the monsoon, how to water before a frost, and why the sprinkler system should not be shut off.
Irrigation Guides5 min read
A Glendale winter watering schedule runs far less often than summer, but it should not stop. AMWUA says much less water is needed in the cool months, and University of Arizona Cooperative Extension advises keeping plants well watered before frost, which arrives across the Phoenix area between late November and mid-December on average.
Glendale winters are mild by most standards, but they still bring frost nights, short days and dormant Bermuda grass. The mistake most yards make is leaving the summer program running into December. The second mistake is shutting the system off completely. This guide sets out the middle path.
When should I switch to a winter watering schedule in Glendale?
Start cutting back after the monsoon ends on September 30 and nights begin to cool, then cut again as frost season approaches. The Arizona Municipal Water Users Association recommends adjusting schedules at least four times a year, and fall and early winter are two of those turns.
The AMWUA watering guidance says far less water is required during the cooler months than in summer. Each watering should still wet the root ball plus one to two inches of the surrounding soil. In winter that means the same depth, with many more days between waterings.
What a winter schedule changes
| setting | summer | winter |
|---|---|---|
| days between waterings | short | much longer; a soil probe decides |
| run time per cycle | set for depth | about the same depth, so similar minutes |
| start time | very early, before the heat | still early, but after the coldest hour is fine on frost-free nights |
| new plants | every 1 to 2 days at first | every 3 to 4 days at first, per AMWUA |
The point is to keep the water deep and make it less frequent. Short, frequent winter cycles keep the surface damp, invite weeds and do little for roots.
Should I turn off my sprinklers in winter in Glendale?
No. Glendale's winters are not cold enough to need the full shutdown and blow-out common in northern states, and many desert plants and trees still need some water. Dormant Bermuda grass needs little, but citrus, shrubs and young plants still draw from the soil between rains.
Lowering the frequency and keeping depth is the better approach. If the controller has a seasonal adjust or water budget setting, it can scale every station at once. Check the result station by station, because a drip zone and a lawn zone respond differently. Our guide to seasonal run times has step-by-step settings.
How should I water before a frost?
Water the day before an expected frost if the soil is dry. University of Arizona Cooperative Extension explains that frost injury happens when ice crystals on the leaf draw moisture from the tissue, and that damage is less severe when the plant is not already drought-stressed.
The Extension frost protection guide puts the average first frost between November 21 in Buckeye and December 12 in central Phoenix, and the last frost between February 7 in central Phoenix and April 3 in Mesa. Glendale, between those points on the west side of the metro, should plan for frost nights through that window. Extension also says moist, firm, bare soil stores and releases more heat than loose, dry or mulched soil.
Covering plants on a frost night
Extension's advice is simple and worth following:
- drape the cover all the way to the ground, with no gaps for warmth to escape;
- use frost cloth where possible, which can stay on for longer stretches;
- remove sheets and blankets in the morning once it warms to about 50 degrees F;
- focus on citrus and young, flowering or dehydrated plants, which are the most vulnerable.
Citrus is the plant most Glendale yards worry about. The citrus watering guide covers its winter interval in detail.
Protecting the sprinkler system from freezing
Glendale's freezes are usually brief, but exposed parts can still crack. The parts most at risk are above ground: the backflow assembly near the house, exposed riser pipes and any drip tubing laid on top of the gravel. Wrap or cover the backflow assembly before the first frost window. If it cracks, the City of Glendale requires a permit and an inspection for any replacement, so prevention is far simpler than repair.
Buried pipe and valves are rarely affected in a typical Glendale frost. Check the system after a hard freeze anyway: run each zone and look for new leaks or a backflow assembly that drips.
Downtown flood-irrigated lots in winter
On lots that take the city's urban flood irrigation, the delivery season ends in late October and does not restart until spring. In 2026 the first delivery was April 6. Trees that relied on those deep floods all summer go into winter on whatever drip or sprinkler system the lot also has, so check that those trees are covered by a winter schedule. The City of Glendale Water Services page explains the urban irrigation system.
Next steps
Set the winter program, write it down, and plan to revisit it in late winter as temperatures rise. A seasonal irrigation tune-up in Glendale can do the reset, check for frost damage and leave the program in writing. If the controller will not hold its settings, see irrigation controller repair in Glendale. The general seasonal irrigation tune-up page explains a visit.
FAQ
How often should I water in winter in Glendale?
- Much less often than summer, with the same depth per watering. AMWUA says far less water is needed in the cooler months. Let a soil probe decide the gap between waterings, and water new plants every three to four days at first, as AMWUA advises.
Should I turn my sprinkler system off for the winter?
- No. Glendale winters do not call for a full shutdown, and many plants still need water. Reduce how often each zone runs, keep the depth, and protect the exposed backflow assembly and above-ground pipes before the first frost.
When is the first frost in the Glendale area?
- University of Arizona Cooperative Extension puts the average first frost between November 21 in Buckeye and December 12 in central Phoenix. Glendale sits between those points on the west side of the metro, so plan for frost nights from late November.
Should I water plants before a frost?
- Yes, if the soil is dry. Extension explains that frost injury pulls moisture from leaf tissue, and drought-stressed plants suffer more. Moist, firm soil also stores and releases more heat than dry or loose soil, which helps on a cold night.
Do I need to winterize my sprinkler system in Glendale?
- Not the way northern states do. Glendale freezes are usually brief, so there is no need to drain or blow out the lines. Cover the backflow assembly and exposed pipes, and check the system for new leaks after a hard freeze.
Sources
- AMWUA watering guidance amwua.org
- Extension frost protection guide extension.arizona.edu
- City of Glendale Water Services page glendaleaz.gov