Arizona · 22 cities · spring 2026

When to apply crabgrass preventer in Arizona

Last spring the soil reached 50°F aroundFeb 1Median of 9 cities; crabgrass temperatures (55°F) followed around Feb 5. Earliest: Bullhead City Jan 14; latest: Flagstaff Mar 16.
Today
Season over
22 of 22 cities
Window last spring
4 days
median gap from 50°F to 55°F
Soil today
69°F
median, 0–4 in
Never below 50°F
13
cities with no spring window

Last spring's pre-emergent window, largest Arizona cities

Each bar runs from the day the soil held 50°F to the day it held 55°F (2026).

FebMarAprMayFlagstaffFlagstaff: Mar 16 to Mar 20Sierra VistaSierra Vista: Feb 1 to Feb 25Prescott ValleyPrescott Valley: Feb 26 to Mar 13Bullhead CityBullhead City: Jan 14 to Feb 1KingmanKingman: Feb 2 to Feb 5SahuaritaSahuarita: Jan 15 to Jan 18NogalesNogales: Jan 16 to Feb 3DouglasDouglas: Jan 16 to Feb 3PaysonPayson: Feb 3 to Mar 12
FebMarAprMayFlagstaffFlagstaff: Mar 16 to Mar 20Sierra VistaSierra Vista: Feb 1 to Feb 25Prescott Va…Prescott Valley: Feb 26 to Mar 13Bullhead Ci…Bullhead City: Jan 14 to Feb 1KingmanKingman: Feb 2 to Feb 5SahuaritaSahuarita: Jan 15 to Jan 18NogalesNogales: Jan 16 to Feb 3DouglasDouglas: Jan 16 to Feb 3PaysonPayson: Feb 3 to Mar 12
Source: NOAA NCEP GFS analyses, 0–10 cm; 5-day mean held 10 days.

Every Arizona city

Spring 2026 dates and today's verdict.

CityHeld 50°F (2026)Held 55°F (2026)Soil todayToday
Phoenix, AZnever belownever below77°FSeason over
Tucson, AZnever belownever below75°FSeason over
Chandler, AZnever belowJan 1471°FSeason over
Surprise, AZnever belowJan 1472°FSeason over
Yuma, AZnever belownever below74°FSeason over
San Tan Valley, AZnever belowJan 1568°FSeason over
Flagstaff, AZMar 16Mar 2045°FSeason over
Lake Havasu City, AZnever belowJan 1570°FSeason over
Casa Grande, AZnever belowJan 1569°FSeason over
Buckeye, AZnever belowJan 1472°FSeason over
Maricopa, AZnever belowJan 1570°FSeason over
Sierra Vista, AZFeb 1Feb 2559°FSeason over

Crabgrass seeds start to germinate once the top 2 to 4 inches of soil stay near 55°F for several days. A pre-emergent works as a barrier in the soil, so it has to be down and watered in before that: the usual advice is to apply it while the soil holds 50 to 55°F. The dates here are when the modelled soil began to hold each temperature last spring; this year's window will move with the weather, which is why each city page shows today's reading and the 7-day forecast.

Questions

When should I put down crabgrass preventer in Arizona?
When the soil holds 50 to 55°F. Last spring that was around Feb 1 to Feb 5 across 9 Arizona cities, earlier in the south and in cities.
Is it too late to apply pre-emergent?
Once the soil has held 55°F for a week or more, crabgrass is germinating and a pre-emergent will not stop the seedlings already up. Each city page says which side of that line it is on today.

Soil temperature today in Arizona →

Data: Global Forecast System (GFS) 0.25°, soil temperature 0–10 cm (TSOIL) (NOAA National Centers for Environmental Prediction (NCEP)); GeoNames gazetteer (cities15000) (GeoNames).