Ho Chi Minh City has two seasons rather than four, and the pest year follows them closely. Termites swarm with the first heavy rains in April or May. Mosquito numbers climb two to three weeks after the rains become regular. Rodents move towards buildings through the dry months from December.
Knowing which half of the year you are in tells you what to look for and what to do about it. These pages cover the year in order.
The year at a glance
- A pest calendar for Ho Chi Minh City — what turns up in each part of the year, and why the dates shift with the rainfall rather than the calendar.
The dry season: December to April
The quietest period for flying insects and the busiest for rodents. Outdoor food and water dry up, construction disturbs the ground, and rats move indoors through refuse chutes, service risers and the gap under a door.
- Rodents: identification and behaviour
- How rodents and insects travel up a tower
- Why kitchens come back from Tet with a problem — closure changes two things at once.
April and May: the termite swarm
- What the flying insects at your window mean — how to tell termites from flying ants, and why the location of the discarded wings matters more than the swarm.
- Termites: what they damage and how they are treated
The rainy season: May to November
Standing water multiplies mosquito breeding sites, humidity speeds up cockroach breeding, and outdoor treatments wash off far faster than in the dry months.
- Rainy season pest control — the three checks that matter most, and why fogging alone disappoints.
- The eleven places mosquitoes actually breed — and why emptying a container is not enough on its own.
- Dengue and the other risks worth taking seriously
- Mosquitoes: species and behaviour
All year: the things that do not follow a season
- Cockroaches · Ants · Flies · House geckos · Spiders · Paederus beetles
- Bed bugs — carried in luggage and second-hand furniture rather than raised by the weather.
Planning around the year
A programme worth paying for changes what it does in April and again in November: exclusion and proofing through the dry months, source reduction and drainage through the rains. One-off treatment or annual contract explains which shape suits which property.
Book an inspection
Site inspections are free of charge and carry no obligation. The best time to book is four to six weeks before a season changes — the same work costs less and takes fewer visits than it does once a problem is visible.
Request an inspection · See indicative prices · All services
What to do in each part of the year
The seasons are predictable here, so the useful version of a pest calendar is not a list of what appears but a list of what to do before it does.
- February to March, before the swarm. If you have timber, ground contact or a garden structure, this is when a termite inspection is worth booking. Once winged termites appear at the lights in April, the colony has already been active for years.
- April to May, before the rains. Clear gutters, downpipes and drainage channels, and empty or invert every container in a garden, balcony or terrace. Ten minutes now removes most of the mosquito production for the following six months.
- June to September, during the rains. Check drainage weekly rather than monthly. After heavy rain expect American cockroaches indoors for a day or two as the drainage system fills — keep floor traps wet and penetrations sealed.
- October to November, as the rain eases. The best window for a general treatment: populations are at their yearly peak, so a treatment now removes the most insects and the effect carries into the dry months.
- December to January, the dry months. Rodent activity moves indoors in search of water. Check the gap under external doors, pipe penetrations and roof junctions, and keep bins closed.
Tet, and the fortnight nobody plans for
The Tet holiday is the single most reliable trigger for a pest complaint in this city, and the reason is structural rather than seasonal: kitchens close, bins sit, buildings empty, and drainage traps dry out over a fortnight of no water use. Restaurants and offices reopen to a problem that developed while nobody was there. The remedy is unglamorous — empty all waste before closing, run water down every drain on the last day, and book the first treatment for the week of reopening rather than a month later. See why kitchens come back from Tet with a pest problem.
Planning a year for a business
For a commercial site the seasons should change the emphasis of a programme rather than its existence: mosquito and drainage work weighted into the rainy months, rodent proofing into the dry ones, and the heaviest general treatment scheduled for October or November. A contract that does exactly the same thing every month costs the same and achieves less. See pest control for businesses in Vietnam.