Tips for Preventing Pest Infestations at Home

Close the Gaps First

Mice can use very small openings, and cockroaches can shelter in narrow cracks. Sealing a confirmed route supports other control work. Walk the accessible perimeter with a flashlight and look at these six places.

• Plumbing penetrations — Where supply and waste lines pass through the wall, especially under kitchen and bathroom sinks. These are usually open, or stuffed loosely with steel wool that has already rusted through.
• Utility conduit entries — Check where cable, electrical, and HVAC lines pass through siding for gaps.
• Garage door bottom seal — A worn rubber seal leaves a gap along the slab, and the garage is the room a rat reaches first.
• Foundation vents — Torn or missing crawl space vent screens open a route for rodents and give subterranean termites cover to work in.
• Door sweeps — Check back doors and garage service doors for worn seals and visible gaps.
• Roof vents and soffits — The way in for roof rats, which are established across Monterey and Santa Cruz counties and get onto roofs from branches and utility lines.

Water Is the Thing They Cannot Do Without

Moisture supports many pests, but it does not explain every infestation. A leak can favor cockroaches, ants, decay fungi, or termites, depending on the species and access. Inspect the foundation, sinks, crawl space, and roof after rain, then repair the actual source of water.

• Fix dripping faucets and weeping pipe joints under sinks the week you notice them.
• Aim sprinkler heads away from the walls so spray lands on planting rather than on the foundation and the siding.
• Ask a qualified contractor whether crawl-space moisture control is needed. A barrier alone will not solve every pest or decay problem.
• Extend downspouts so gutter water leaves the foundation instead of pooling against it.
• Repair roof leaks before the next rainy season. Wet roof framing is what dampwood termites and carpenter ants are looking for.

The Yard Decides What Reaches the House

Vegetation, stored materials, and food sources near a structure can shelter pests or hide entry points. Walk the perimeter so walls and vents remain visible and repairs are possible.

• Wood touching soil — Raised planters, fence posts, deck framing, and wood bed borders in contact with the ground give subterranean termites a covered path into the structure. Keep at least six inches of clear air between any wood and the soil.
• Ivy and dense ground cover — A mat of ivy against the foundation is rodent housing with a roof on it. Both Norway rats and roof rats nest in it, and it hides the wall so you cannot inspect what is behind it.
• Firewood against the wall — Store wood away from the building and inspect it before bringing it inside.
• Branches touching the roofline — Roof rats walk overhanging limbs onto the roof and work from there to a vent or soffit gap. Cut back so nothing reaches the eave.
• Bird feeders close to the wall — Spilled seed feeds mice and Norway rats. Put the feeder well out in the yard and sweep under it.

The Central California Pest Calendar

Seasonal activity varies by weather and species. Use this calendar as a reminder to inspect, not a prediction that a particular pest will arrive in a particular month.

• After warm rain — Check for subterranean termite swarmers or discarded wings and preserve a sample for identification.
• After changes in moisture — Follow Argentine ant trails and check irrigation, leaks, and entry points.
• Late summer and fall — Watch for drywood termite swarmers and increased yellowjacket foraging near outdoor food.
• Before wet weather — Check door sweeps and vents for rodent access, especially if there are fresh signs nearby.
• Through winter — Inspect indoor food and water sources if cockroaches or other pests remain active.

Food Storage That Does Not Feed a Colony

Store dry goods in hard-sided airtight containers rather than the bag or box they came in, and that includes flour, cereal, rice, nuts, birdseed, and pet food. Cardboard and plastic film stop nothing. Empty trash before the bag is full, rinse food residue out of recycling, and take pet bowls up overnight. Once a year, pull the stove and the refrigerator out and clean the floor and the coils behind them, because the grease and crumbs collecting under a range will support a cockroach population by itself.

Where Prevention Runs Out

Housekeeping and exclusion reduce some risks but cannot reveal hidden termite activity or control every nearby ant colony. If signs continue, document them and request an inspection that names the pest, accessible areas, and limits of what was seen.