An empty house in Tucson between May and October is a different animal than an empty house anywhere else. Swift Pest gets the same call every October from homeowners coming back to roach activity in a guest bathroom, a scorpion in the laundry room, or chewed wiring in a car that sat all summer. Almost none of it happens because the house was dirty. It happens because nobody was there for four months while the monsoon came through, the drains dried out, and small openings went unnoticed.
Why do the drains matter more than anything else?
Every drain in your house has a P-trap, the U-shaped bend that holds a plug of water and blocks sewer gas and insects from coming up the pipe. In Tucson’s dry summer air, the water in a trap that goes unused can evaporate in three to six weeks. Once it does, the pipe is an open tunnel from the sewer line into your house.
American cockroaches, the large ones people call sewer roaches or palmetto bugs, travel municipal sewer lines and come up through dry traps. So do drain flies. The guest bathroom, the laundry standpipe, a garage floor drain, and a rarely used tub are the usual culprits.
Before you leave, run every fixture for a minute, then pour a few tablespoons of mineral oil or cooking oil into each trap. The oil floats on the water and slows evaporation for months. Cover unused floor drains.
Should I turn the air conditioning off completely?
Leave it running at a setback temperature rather than shutting it off. Somewhere in the low to mid 80s keeps interior humidity down during monsoon season and keeps air moving, and it protects drywall, cabinetry, and electronics from weeks at 110 degrees indoors.
If you run an evaporative cooler, drain it, shut off the water supply, and cover it. A reservoir sitting for four months is a mosquito nursery on your roof.
What outside is going to cause problems?
Standing water and unattended irrigation. Aedes aegypti mosquitoes, established in Tucson, will breed in a container holding as little as a bottle cap of water, and Pima County’s vector control program treats untended green pools as a public health issue. Empty plant saucers, buckets, wheelbarrows, and tires. Arrange for pool service to continue while you are gone rather than pausing it.
Irrigation is the quieter one. A cracked drip line or stuck emitter can run unnoticed for months, and constant moisture at the foundation draws crickets, roaches, and eventually the scorpions that hunt them. Reduce the timer to a summer-appropriate schedule and have someone walk the system once a month.
What should come out of the pantry and garage?
Anything with grain in it. Pantry pests like Indian meal moths and flour beetles complete a full generation in about four to six weeks at summer temperatures, so a forgotten bag of flour, birdseed, dog food, or rice can turn into a widespread infestation while you are away. Take it with you, freeze it, or seal it in glass or hard plastic. Cardboard and thin bags will not hold.
In the garage, break down and remove cardboard boxes, which double as roach harborage and pack rat nesting material. If a car is staying behind, pack rats will use the engine compartment and chew wiring. Park it away from block walls and desert landscaping, and consider leaving the hood open where the space is enclosed.
How do I close the gaps before I go?
Walk the exterior and look at the bottom of every exterior door. Bark scorpions, the only medically significant scorpion species in the United States and common throughout Tucson, can pass through a gap roughly the thickness of a credit card. Door sweeps and weatherstripping are the highest value hour you will spend.
Also check window screens for tears, screen the attic and dryer vents, and seal gaps where conduit, hose bibs, and the AC lineset penetrate the wall. Vacant houses are quiet, undisturbed structures, which is exactly what a honeybee swarm looks for in a wall void or water meter box during spring swarm season.
What should Swift Pest be doing while you are gone?
Exterior perimeter service on a regular interval is the core of it, since nobody is inside to notice a problem developing. Swift Pest sets a schedule for absent homeowners that generally includes:
- A pre-departure inspection and treatment two to four weeks before you leave
- Exterior perimeter applications every 60 to 90 days through the summer
- Attention to the monsoon window in July and August, when scorpion and cricket pressure spikes
- An interior check if you can leave access with a neighbor, property manager, or family member
- A return visit timed to your arrival so the house is treated before you unpack
Recurring exterior service in the Tucson area commonly runs in the $70 to $130 per visit range depending on lot size and structure.
Before you lock the door
Empty the trash and rinse the bins, hold your mail through USPS rather than letting it pile up, and give someone local a key. Most summer pest problems are moisture problems that went unwatched, and a house that gets checked once a month rarely produces a bad surprise in October.
Get on the schedule with Swift Pest before you head north, and come back to a house you can walk into without a flashlight and a shoe in your hand.