Living in Arizona’s East Valley — including Scottsdale, Mesa, Gilbert, Fountain Hills, Chandler, Paradise Valley, and Rio Verde — means dealing with pest pressures that are dramatically different from the rest of the country. Our Sonoran Desert climate creates year-round pest activity, but the types of pests and their intensity shift significantly from month to month.
At Cummings Termite & Pest, we’ve spent over 50 years protecting East Valley homes. This month-by-month pest calendar is based on decades of field experience and will help you stay one step ahead of the pests that threaten your property and family.
Winter: January Through March
Many homeowners assume winter means a break from pest activity. In Arizona, that’s only partially true. While some pests slow down, others become more problematic as they seek warmth and shelter inside your home.
January: Overwintering Pests and Early Weed Growth
January nights in the East Valley dip into the 30s and 40s, pushing pests indoors. Roof rats, house mice, and other rodents are especially active, seeking food and warmth in attics, garages, and wall voids. Rodent activity peaks during this period as natural food sources decline.
Bark scorpions enter a state of reduced activity but don’t truly hibernate. They cluster in sheltered spots — inside block walls, behind baseboards, and in closets — and can still sting if disturbed. Crickets and occasional roaches may also appear indoors.
Winter weeds like London rocket, stinknet (globe chamomile), and filaree begin germinating after fall and winter rains. Left unchecked, these weeds create harborage for insects and scorpions. Pre-emergent weed treatments applied in late fall should be actively working now.
Homeowner action items:
- Inspect your attic and garage for rodent droppings or gnaw marks
- Seal gaps around pipes, utility lines, and garage door weather-stripping
- Remove fallen citrus and other food sources from your yard
- Check that pre-emergent weed treatment is holding; apply post-emergent spot treatments as needed
February: Early Termite Swarms and Ant Activity
February marks the beginning of subterranean termite swarming season in Arizona. After winter rains, reproductive termites (alates) emerge from mature colonies to start new ones. You may notice small, winged insects near windows, light fixtures, or emerging from the soil around your foundation.
Ant colonies also begin expanding. Harvester ants, fire ants, and odorous house ants become more visible as foraging activity increases with warming daytime temperatures.
Homeowner action items:
- Watch for small wings shed near windowsills or light sources — a sign of termite swarmers
- Schedule a professional termite inspection if your home hasn’t been inspected in the past year
- Keep mulch and wood debris away from your foundation
- Address moisture issues around your home’s perimeter (leaking hose bibs, over-irrigated landscaping)
March: Transition Month — Activity Ramps Up
March is when the pest calendar begins its dramatic shift. Daytime temperatures regularly reach the 80s, triggering increased activity across nearly every pest category. Termite swarms continue. Bee colonies begin scouting for nesting locations, and scorpion activity starts to increase as nighttime temperatures rise above 60°F.
This is the most important month for preventive action. Barrier treatments applied now create a protective perimeter around your home before the spring and summer surge.
Homeowner action items:
- Schedule a comprehensive pest inspection and barrier treatment
- Inspect exterior walls, eaves, and utility boxes for early bee activity
- Clear yard debris, rock piles, and woodpiles that harbor scorpions and spiders
- Begin UV flashlight inspections at night for scorpions
Spring: April Through June
Spring in the East Valley is when pest pressure reaches its first major peak of the year. Warmer temperatures and longer days create ideal conditions for explosive population growth across multiple pest species.
April: Scorpion Season Begins in Earnest
April marks the unofficial start of scorpion season. Arizona bark scorpions emerge from their overwintering sites and begin actively foraging for prey — primarily crickets and other small insects. Homes near desert preserves in Scottsdale, Fountain Hills, and Rio Verde experience the highest scorpion pressure.
Ant colonies are in full expansion mode. You may see foraging trails along foundations, driveways, and interior baseboards. Fire ants become especially aggressive, and their painful stings pose a risk to children and pets playing in the yard.
Homeowner action items:
- Begin monthly scorpion treatments if you live near desert areas
- Use a UV (blacklight) flashlight to inspect around your home at night
- Seal all entry points: door sweeps, window screens, plumbing penetrations, and expansion joints
- Treat ant mounds before colonies mature and spread
May: Peak Termite Swarming and Bee Swarms
May is one of the busiest months in Arizona pest control. Subterranean termite swarms peak, and homeowners frequently discover mud tubes along foundations, in garages, and around plumbing penetrations. This is the month when many infestations are first detected.
Africanized honey bees are actively swarming and establishing new colonies. Swarms may temporarily land on trees, fences, or structures before moving on, but established hives in walls, eaves, or irrigation boxes require professional removal. Africanized bees are significantly more aggressive than European honey bees and pose a real danger.
Homeowner action items:
- Do not disturb bee swarms — call a professional immediately
- Schedule a termite inspection if you see wings, mud tubes, or frass
- Ensure exterior barrier treatments are current
- Keep trash bins sealed and pet food indoors to reduce ant attractants
June: Extreme Heat Drives Pests Indoors
As temperatures soar past 110°F, many pests seek refuge in the cooler, more humid environment of your home. Scorpion activity is at its peak. Crickets, roaches, and other prey insects are drawn to irrigated landscapes, which in turn attracts more scorpions.
Spiders — including black widows and brown spiders — become more visible in garages, sheds, and undisturbed areas. Summer weed species like spurge, puncturevine, and Bermuda grass begin aggressive growth.
Homeowner action items:
- Maintain monthly pest treatments through the summer
- Reduce exterior lighting that attracts insects (or switch to yellow “bug” bulbs)
- Inspect shoes, bedding, and clothing in closets near exterior walls for scorpions
- Apply post-emergent weed treatments to summer weeds before they seed
Monsoon Season: July Through September
Arizona’s monsoon season — typically mid-June through September — transforms the pest landscape. Sudden humidity spikes, standing water, and cooler evening temperatures create a perfect storm of pest activity.
July: Monsoon Moisture Triggers Pest Explosions
The arrival of monsoon storms brings a dramatic increase in pest activity. German cockroaches and sewer roaches (American cockroaches) become extremely active, driven out of storm drains and sewer systems by flooding. Crickets hatch in enormous numbers, providing an abundant food source that fuels scorpion population growth.
Roof rats remain active in citrus trees and palm trees, and monsoon damage to roofing and soffits can create new entry points. Snake activity increases significantly as they follow prey drawn out by the rains.
Homeowner action items:
- Eliminate standing water around your property after storms
- Check roof and soffit for storm damage that could allow pest entry
- Keep exterior doors closed — roaches and crickets are attracted to indoor lights
- Trim palm tree skirts and citrus tree canopies to reduce rodent harborage
August: Peak Monsoon Pest Pressure
August typically sees the highest monsoon activity and corresponding pest pressure. Scorpion encounters inside homes peak during this period. The combination of cricket hatches, roach activity, and continued high temperatures keeps all predatory pests — scorpions, spiders, and centipedes — extremely active.
Bats are also very active during monsoon season, feeding on the explosion of flying insects. While beneficial for insect control, bat colonies in attics or walls create health concerns from guano accumulation.
Homeowner action items:
- Ensure all door sweeps and window screens are intact
- Inspect attic for bat entry points (look for guano stains and urine streaks)
- Continue monthly pest barrier treatments
- Address any drainage issues that create standing water
September: Transition Out of Monsoon Season
Monsoon storms taper off in September, but pest activity remains high. Scorpion mothers give birth to live young in late summer, meaning smaller juvenile scorpions may appear in greater numbers. Roof rat activity begins to increase as they sense seasonal changes and start seeking nesting sites for winter.
September is also an important month for pre-emergent weed treatments to prevent the fall germination of winter weeds.
Homeowner action items:
- Apply pre-emergent weed treatments before October rains
- Inspect and seal any new gaps or cracks that developed during monsoon storms
- Trim vegetation away from your home’s exterior
- Schedule a fall pest inspection to assess post-monsoon conditions
Fall: October Through December
As temperatures cool, the pest landscape shifts again. Some pests become less active, while others increase their efforts to move indoors before winter arrives.
October: Rodents Move Indoors
October is prime time for rodent invasions. Roof rats and house mice begin seeking indoor shelter as nighttime temperatures drop. They can enter through gaps as small as a quarter (rats) or a dime (mice). Once inside, they contaminate food, gnaw on wiring (creating fire hazards), and reproduce rapidly.
Scorpion activity begins to decrease as temperatures cool, but they’re still active on warm evenings. Bee colonies that established during spring and summer are now mature and well-defended.
Homeowner action items:
- Inspect your roof, soffit, and eaves for rodent entry points
- Trim tree branches that overhang or touch your roof
- Store food in sealed containers and clean up pet food at night
- Consider rodent exclusion services for long-term prevention
November: Reduced Activity but Continued Vigilance
November brings welcome relief from many pest pressures, but it’s not a time to let your guard down. Rodent activity continues to increase as they settle into indoor nesting sites. Termites remain active underground year-round — they don’t stop feeding just because it’s cooler.
Winter weeds begin their primary germination period. London rocket, stinknet, and other invasive species take advantage of fall rains and mild temperatures.
Homeowner action items:
- Verify pre-emergent weed treatments are in place before winter rains
- Continue quarterly pest maintenance to keep barrier treatments effective
- Check attic insulation for signs of rodent nesting
- Schedule a year-end termite inspection
December: Year-End Review and Prevention Planning
December is the quietest month for pest activity in the East Valley, but it’s the ideal time for planning and prevention. Rodents are your primary indoor concern. Occasional scorpion sightings still occur in heated homes. Overwintering insects like boxelder bugs and occasional invaders may cluster on south-facing walls during warm afternoons.
This is also the best time to evaluate your annual pest management plan and make adjustments for the coming year.
Homeowner action items:
- Review your annual pest management results
- Schedule a comprehensive home pest inspection for early January
- Address any structural issues (cracks, gaps, damaged screens) before spring
- Plan your pest management budget for the year — monthly service during scorpion season and quarterly service for general pest prevention
Year-Round Pest Prevention Tips for East Valley Homes
Regardless of the season, certain practices will significantly reduce your pest risk:
- Seal entry points: Caulk cracks around windows, doors, pipes, and utility penetrations. Install door sweeps on all exterior doors.
- Manage moisture: Fix leaky faucets, adjust irrigation to avoid overwatering near foundations, and ensure proper drainage.
- Reduce harborage: Keep landscaping trimmed away from the home. Remove woodpiles, rock piles, and debris where pests shelter.
- Eliminate food sources: Clean up fallen fruit, secure trash cans, and bring pet food indoors at night.
- Maintain your barrier: Professional perimeter treatments are most effective when maintained on a regular schedule — monthly during high-activity seasons and quarterly during cooler months.
Why East Valley Homeowners Trust Cummings Termite & Pest
With over 50 years of experience serving the East Valley, Cummings Termite & Pest understands the unique pest challenges that come with desert living. Our technicians live and work in the communities we serve — from Scottsdale and Fountain Hills to Gilbert, Mesa, Chandler, Paradise Valley, and Rio Verde.
We offer customized pest management plans that adapt to seasonal changes, ensuring your home is protected every month of the year. Whether you need scorpion control, termite treatment, rodent exclusion, or weed management, our team has the expertise and local knowledge to deliver results.
Schedule your seasonal pest inspection today and start the year with complete peace of mind.
Frequently Asked Questions
What month do scorpions come out in Arizona?
Arizona bark scorpions become significantly more active starting in April when nighttime temperatures consistently exceed 60°F. Their activity peaks during the monsoon season (July through September) when cricket and insect populations explode, providing abundant prey. However, scorpions can be found inside homes year-round in the East Valley, especially in heated structures during winter months.
When is termite season in Arizona?
Subterranean termite swarming season in Arizona runs primarily from February through May, with the peak occurring in April and May after spring rains. However, termites are active underground 365 days a year in our climate. Swarming season is simply when you’re most likely to notice an infestation because the winged reproductive termites become visible.
Do I need pest control in Arizona during winter?
Yes. While overall pest activity decreases in winter, rodents become more problematic as they move indoors seeking warmth, termites remain active underground, and overwintering scorpions can still be found inside homes. Quarterly maintenance treatments during winter months maintain the protective barrier around your home and prevent spring pest populations from establishing early.
What pests are worst during Arizona monsoon season?
Monsoon season (July through September) triggers major activity from cockroaches (driven from storm drains by flooding), crickets (massive hatches from monsoon moisture), scorpions (following the prey explosion), roof rats, snakes, and flying insects. The combination of heat and sudden humidity creates ideal conditions for rapid pest population growth.
How often should I get pest control in the East Valley?
For most East Valley homes, quarterly pest treatments provide solid baseline protection. However, homes near desert preserves — particularly in Scottsdale, Fountain Hills, and Rio Verde — typically need monthly treatments during scorpion season (April through October) for adequate protection. Cummings Termite & Pest can assess your specific property and recommend the right treatment frequency.