Termite season in New Orleans runs roughly from February through July, with the most intense activity happening in May and June when Formosan subterranean termites swarm by the millions on warm, humid nights. The city is home to several termite species, each with its own schedule, but the Formosan termite is the one that dominates local conversation and causes the most damage.
Which Termites Swarm and When
New Orleans hosts multiple subterranean termite species, and their swarm windows overlap in a way that keeps the threat active for months. Eastern subterranean termites are the earliest, swarming from February through May, typically in the morning hours. The dark southeastern subterranean termite swarms during the day in March and June. Then the Formosan termite takes over in late spring, swarming at night from May through July. A less common species, the light southeastern subterranean termite, swarms during daylight hours in the fall, extending the overall season even further.
Of all these, the Formosan termite is the species that defines termite season in New Orleans. Colonies can contain millions of individuals (compared to hundreds of thousands for native species), and they consume wood far faster. A single Formosan colony can cause serious structural damage within a few years if left unchecked. When locals talk about “termite season,” they’re almost always talking about the Formosan swarm nights that peak in May and June.
What Triggers a Swarm
Formosan swarms are driven by a specific combination of weather conditions. The triggers are warm temperatures, high humidity, and recent rainfall. A hot, rainy day followed by a still, muggy evening is the classic recipe. When those conditions hit, winged reproductive termites (called swarmers or alates) leave their colonies by the thousands to mate and establish new colonies. In New Orleans, these swarm events tend to happen after sunset, often between 8 and 10 p.m., and they can be dramatic enough to look like clouds under streetlights.
Not every warm night produces a swarm. The insects seem to coordinate around specific weather patterns, so you might go a week or two without seeing any, then get hit with several heavy swarm nights in a row after a stretch of rain.
How to Handle Swarm Nights
Formosan termites are intensely attracted to light. On swarm nights, your porch lights, yard lights, and even bright indoor lighting act as beacons that draw swarmers directly to your home. The single most effective thing you can do during peak season is manage your lighting.
- Turn off all non-essential outdoor lights. Porch lights, landscape lighting, and garage lights should stay off on warm, humid evenings from May through early July.
- Close curtains and blinds. Bright indoor lights visible through windows attract swarmers just as effectively as outdoor fixtures. Dimming interior lights or blocking them from view helps significantly.
- Seal entry points. Formosan termites come in through vents, gaps under doors, and any small opening. Weather stripping and door sweeps reduce the number that make it inside.
- Check the next morning. Look for piles of discarded wings on windowsills, near doors, or around light fixtures. Wings left behind are a sign that swarmers landed at your home and may have begun looking for places to start new colonies.
Finding a few swarmers inside your house on a big swarm night isn’t necessarily a sign of an existing infestation. They’re often drawn in by light and die quickly indoors. But finding large numbers of swarmers emerging from your walls, ceiling, or floors is a different story entirely.
Signs of an Active Infestation
Swarmers appearing inside your home during the day or emerging directly from the structure itself (not just flying in through an open door) are one of the strongest indicators of an established colony living in or under your house. Beyond swarmers, there are several physical signs to watch for year-round.
Mud shelter tubes are the most recognizable. These are pencil-width tunnels made of soil and saliva that termites build along foundation walls, support piers, and plumbing lines to travel between their underground colony and the wood they’re feeding on. You’ll find them on exterior foundation walls, inside crawl spaces, and sometimes on interior walls or ceilings. Formosan termites also build what are called “swarm castles,” odd-shaped formations of dried mud that sprout from walls or ceilings in late spring as the colony prepares to release swarmers.
Subtler signs include BB-sized spots of dried mud on interior walls or ceilings (pinholes where termites have broken through drywall), narrow sunken lines in paint or wallpaper where termites have eaten the material behind the surface, and sagging floors or door frames that no longer close properly. If you peel back wallpaper or open up a wall during a renovation and find hollowed-out wood with soil packed into the channels, that’s active or recent termite damage.
Drywood termites, a separate species, leave behind small six-sided pellets that accumulate on floors or countertops beneath “kick-out holes.” These are less common in New Orleans than subterranean species but worth knowing about.
What Damage Can Cost
Termite damage repair costs vary widely depending on how long the colony has been active and where the damage is located. Cosmetic repairs, like replacing chewed-up trim or patching drywall, can run from a few hundred dollars to a couple thousand. Advanced structural damage, where load-bearing wood has been compromised, averages around $3,000 and can climb well above that for severe cases. Really extensive infestations that affect floor joists, roof supports, or multiple areas of the home push costs into five figures.
The financial risk is compounded by the fact that most homeowner’s insurance policies in Louisiana do not cover termite damage, treating it as a maintenance issue rather than a sudden loss. That makes prevention and early detection the only real financial protection.
Prevention Beyond Swarm Season
Light management during swarm nights keeps new queens from targeting your home, but protecting against established colonies requires year-round attention. Moisture is the biggest factor. Subterranean termites need contact with soil moisture to survive, so anything that keeps your home’s foundation and framing dry reduces your risk. Fix leaky faucets, air conditioning drains, and downspouts that dump water near the foundation. Make sure crawl spaces have adequate ventilation.
Wood-to-soil contact is the other major invitation. Mulch piled against the foundation, wooden lattice touching the ground, firewood stacked against the house, and fence posts connected to the structure all give termites a direct path in. Keep at least several inches of clearance between soil and any wooden element of your home.
Professional termite treatments, whether bait systems or liquid soil treatments, are standard practice for New Orleans homeowners. Most pest control companies in the area recommend annual inspections at minimum, ideally timed before the May swarm season begins. Given that a mature Formosan colony can do serious damage in a relatively short time, catching activity early is far cheaper than repairing what they leave behind.