How often do you need pest control, and when in the year?

Updated November 10, 2026 · KeystoneProGuide editorial team

Is there a recommended schedule for pest control?

No agency read for this guide sets one. The EPA's integrated pest management approach ties treatment to what is found, not to the calendar: monitor and identify the pest, decide whether its numbers or the conditions justify action, prevent first, and treat when monitoring shows it is needed. Sighting a single pest, it says, does not always mean control is needed.

Monthly and quarterly plans are common, and HomeAdvisor lists prices for both. Before signing one, the National Pesticide Information Center suggests asking whether a long-term contract is required and what it costs over time, and Penn State Extension suggests asking whether more treatments will be needed and how often. By the EPA's description, a plan built on inspection and monitoring is closer to integrated pest management than one that treats on a fixed date whatever is found.

When do termites show themselves?

In late winter and spring. Penn State Extension says swarms of winged termites in Pennsylvania usually emerge between February and June, often near doors and windows, and that the shed wings left behind are frequently the only sign. That is the season to watch basements and windowsills.

For prevention, the EPA advises periodic inspection, keeping soil by the foundation dry and firewood away from the house. Neither the EPA nor Penn State gives a fixed interval for termite inspections. If a home has been treated, Penn State says to keep the warranty for at least one to two years to see whether the treatment worked, and says yearly renewal fees are common.

When are ticks and mosquitoes active?

For most of the year. The Pennsylvania Department of Health says ticks are most active from April to August and again in October and November, and that they may be active whenever the temperature is above freezing. The Department of Environmental Protection puts peak mosquito season at usually April through October.

For mosquitoes, the useful work is weekly and seasonal: emptying standing water from containers, birdbaths and pools. DEP's advice includes having clogged gutters cleaned every year.

When should you deal with a wasp or yellowjacket nest?

Early, or not at all. Penn State Extension says paper wasps, yellowjackets, hornets and bumble bees start new colonies in late spring or early summer and their colonies die off over winter. A nest found in May or June may be small enough to ignore but could become a problem by August or September, and dealing with it while it is small is safer and easier. A nest found in fall, it says, will perish soon anyway, so management may not be necessary.

When do carpenter ants appear?

In spring and summer. Penn State says winged carpenter ants leave established colonies on warm days in spring and early summer, and suggests looking for foraging workers at night, from May through July, in the basement, attic, garage and outside, to trace them back to a nest.

When do stink bugs come in?

In early autumn. The EPA says adult brown marmorated stink bugs look for winter shelter then and are often found on the outside of buildings or inside near doors and windows. The time to seal gaps and fit door sweeps is before they arrive; once inside, the EPA says sprays will not stop more emerging from cracks.

When is spotted lanternfly season?

Most of the year, in stages. Penn State Extension says eggs are laid from September to December and hatch from late April to June, and adults appear in July and stay active until hard freezes. Penn State advises checking for egg masses, including under vehicles and in wheel wells, from fall to summer, and for nymphs and adults during the growing season.

When should bats be excluded?

Not in early summer. The CDC says most bats leave in fall or winter, which makes those the best times to bat-proof a home, and warns that excluding bats between May and August can trap young bats inside.

What does a year look like?

What should you do between visits?

Prevention. The EPA's termite guidance lists the steps that last all year: fix leaks, keep gutters and downspouts working, keep vents clear, keep plants away from exposed wood and stack firewood away from the house. The signs that should prompt a call are in signs you need pest control, and what a visit involves is in what to expect. Prices for plans are in the cost guide.

Sources

1. Integrated Pest Management (IPM) Principles, U.S. Environmental Protection Agency
2. Selecting a Pest Control Company, National Pesticide Information Center
3. Choosing a Qualified Pest Management or Lawn Care Company, Penn State Extension
4. Eastern Subterranean Termites, Penn State Extension
5. Learn More About Ticks, Pennsylvania Department of Health
6. Department of Environmental Protection to Conduct Mosquito Control in Delaware County, Pennsylvania Department of Environmental Protection
7. Getting Rid of Paper Wasps, Yellowjackets, and Other Stinging Insects, Penn State Extension
8. Brown Marmorated Stink Bug, U.S. Environmental Protection Agency
9. Spotted Lanternfly Management Guide, Penn State Extension
10. Carpenter Ants, Penn State Extension
11. Preventing Rabies from Bats, U.S. Centers for Disease Control and Prevention
12. Termites: How to Identify and Control Them, U.S. Environmental Protection Agency
13. How Much Does Pest Control Cost in 2026?, HomeAdvisor