How long pest control lasts depends on many factors. Pest pressure can vary between houses. Some homes never get pests inside and do not use pesticides. While others often need pest control. Many websites state that pest control lasts 60 or 90 days. This is a very generalized statement. They base this on the residual of the products used, not on the control achieved from the products used.
Manufacturers market pesticides to kill insects for up to 60 or 90 days. This is true in a laboratory setting. It doesn’t really hold up for that long when applied in and around the home. Let’s say you spray a product in a cool, dark and dry basement. This will kill insects much longer than the same thing sprayed outside during a 90 degree summer day. As popular as it is to spray the foundation, you really only get a few days to a week out of that type of application.
Although we apply a band around the foundation, we also apply spray under the bottom lip of the siding. This area is where most pests enter the home. It is also shaded from the sun and rain. Pesticides break down by heat, moisture and UV light. Moreover, pests are less likely to die when they cross over dried pesticides. Pests have to spend time with the pesticide for it to have an effect on them. That is why we apply pesticides to the crevices in which pests enter homes and the crevices in which they hide. These are also areas protected by the elements. So the products work better and for a longer time.
The whole pest control lasting 60 or 90 days is more of a marketing ploy. If you are basing that on how long of a residual a pest control spray has, I would lean more towards the 20 day mark. Once you factor in environmental factors, 20 some days is a good number. Dusts applied to cracks and crevices last much longer. Organic pest management uses a lot of dust since organic sprays hardly have any residual at all. Dusting is usually done once a year.
Sometimes sprays aren’t used at all. So it makes the 60 or 90 day statement pretty irrelevant. For example, you might put out ant or cockroach bait. While the bait may dry up in one week, it can have lasting effects. Yet how long it works for, is a result of how much pest pressure there is, along with many environmental factors.
Your ant bait might knock out the ant nest in your window, but it won’t kill the super colony underneath the driveway. It might take a year for the colony to reestablish a nest in that same window. Unless you perform many treatments to knock a colony back, they will reoccupy the same areas.
One example is if you have carpenter ants in your home during winter. Any carpenter ant nests inside your home consist of workers and older larvae. The queen is in a tree outside. You can kill the ants inside. The main colony will send out more ants to the nest inside your home once the pesticide wears out. So you really need a second service to treat the trees outside during the summer.
Another example is for bed bugs. They hitchhiked inside from somewhere. Our service might eradicate the bed bugs inside of your home. If you introduce another bed bug inside, then pest control will not last as long.
Same thing goes for spiders. You might be getting spiders from leaving the porch light on. We can spray and kill what is there. But if you keep leaving the porch light on, the treatment won’t last as long as it should.
As you can see, pest pressure dictates how long pest control will work, not how long a bug spray can kill bugs for. We recommend treatments every other month during the spray season (March- November). It usually takes a couple months for pests to reoccupy the treatment areas. That is why our warranties are for 60 days. We try to educate our customers and teach what they can do to keep common pests from coming back.