Why Are There So Many Wasps Around My House in Late Summer and Fall?
If it feels like wasps suddenly appear everywhere around your home in late summer and early fall, you’re not imagining it. This is typically when wasp colonies are at their largest, meaning more workers are out searching for food and more activity is noticeable around decks, patios, garbage bins, gardens, and the exterior of your home.
In Canada, wasp activity generally begins in spring and increases throughout the summer. By late summer and early fall, colonies can reach peak numbers before colder temperatures eventually bring the season to an end. That seasonal cycle is one of the main reasons homeowners tend to notice far more wasps at this time of year.
Why Do Wasps Become More Noticeable in Late Summer?
A wasp colony usually starts small in the spring. A fertilized queen emerges from an overwintering location, establishes a nest and begins producing workers. As those workers mature, they help expand the nest, collect food and care for developing young.
Throughout the summer, the colony continues to grow. By late summer, there may be a significant number of worker wasps leaving and returning to the nest throughout the day. Simply put, a larger colony means more wasps flying around your property.
Wasps may also seem more persistent around people at this time of year because they are actively searching for food. Sweet foods, fruit, juice, soft drinks, garbage and food scraps can all attract foraging wasps. Health Canada notes that wasps are commonly attracted to sweet foods, while some species also scavenge around garbage containers.
What Is Attracting Wasps to Your Property?
Your home and yard may offer wasps exactly what they are looking for: food, shelter and a suitable location for a nest.
Common attractants include:
- uncovered garbage and food waste
- recycling containers with sugary residue
- outdoor meals, barbecues and spilled drinks
- ripe or fallen fruit
- other insects and spiders that wasps prey on
- dense shrubs and vegetation
- sheltered areas around the exterior of the house
- existing holes or cavities in the ground
A property with several of these conditions may naturally see more wasp activity, particularly during the latter part of the summer.
Where Do Wasps Build Nests Around a House?
One reason homeowners should pay attention to repeated wasp activity is that the nest itself may not be obvious.
Depending on the species, wasps can nest in or around:
- roof eaves and soffits
- openings in siding
- wall cavities
- sheds and garages
- attics
- door and window frames
- decks and fences
- trees and shrubs
- hollow trees
- holes or abandoned burrows in the ground
Paper wasps often attach exposed nests to areas such as eaves, exterior framing or branches. Yellow jackets and hornets may establish nests in more concealed areas, including wall voids, attics, sheds or underground locations.
From a home-maintenance perspective, repeated wasp activity around one particular section of a house deserves attention.
Watch for Repeated Traffic Around the Same Opening
Seeing the occasional wasp in your yard does not necessarily mean there is a nest attached to your home.
A more telling sign is repeated traffic.
If several wasps continually fly into and out of the same opening, there may be a nest inside or behind that area. Pay particular attention around soffits, roof edges, siding joints, vents and other exterior penetrations.
Those small openings may also be worth noting for another reason: gaps around the exterior can allow insects and other pests to enter protected spaces within the building.
However, do not simply seal an opening if wasps are actively using it. Orkin Canada warns that sealing an active nest inside a structure can cause wasps to find another way out — potentially into the living space of the home.
If you suspect an active nest inside a wall, soffit or attic, professional pest-control advice is the safer approach.
Are Wasps Dangerous?
Wasps are not automatically a problem simply because they are present. They also play a useful role in the ecosystem by feeding on insects and acting as pollinators.
The concern increases when a nest is located close to entrances, decks, walkways, play areas or other frequently used parts of the property.
Social wasps can defend their nests when they perceive a threat, and unlike honeybees, wasps can sting more than once. Health Canada advises seeking immediate medical attention if a sting causes symptoms such as unusual swelling, dizziness or shortness of breath.
How Can Homeowners Reduce Wasp Activity?
You cannot prevent every wasp from visiting your property, but a few maintenance habits may make your home less attractive to them.
Keep garbage containers tightly closed and clean up outdoor food and drink spills promptly. Rinse recycling containers so sugary residue does not accumulate, and remove fallen fruit from the yard.
It is also worthwhile to keep shrubs and vegetation maintained and periodically inspect the exterior of your home for openings around windows, doors, soffits and vents.
Damaged screens and obvious exterior gaps can generally be repaired as part of routine home maintenance — provided there is no active nest inside the area.
Fall Is a Good Time to Look Closely at Your Home’s Exterior
Wasps may be a nuisance, but their activity can sometimes draw your attention to areas of the house you might otherwise overlook.
If wasps repeatedly disappear behind siding, enter a soffit opening or travel through another exterior gap, take note of the location. Once any active nest has been professionally addressed, the opening itself may need repair or sealing to reduce the chance of future pest entry.
Regularly examining roof edges, soffits, siding, vents, windows, doors and other exterior components is an important part of maintaining a home.
And if you are purchasing a property, a professional home inspection can help identify visible defects, gaps, deterioration and other conditions around the exterior that may require maintenance.
AceTec Home Inspections provides professional home inspection services to help homeowners and buyers better understand the condition of a property and the maintenance items that deserve attention.
