It's that time again: soon our gardens will be full of flowers and our kitchens full of ants. Only one of these developments is welcome.
Ants are, in some ways, the dominant creatures on the planet. There are, by one estimate, 20 quadrillion ants on planet earth. That's 12 megatons of biomass, weighing more than every wild bird and mammal combined. So it probably shouldn't be surprising when ants show up in our homes — but that doesn't make it any more pleasant.
And we have all kinds of weird ideas about ants in our home. Some people think an ant showing up means your house is dirty (not necessarily), while others think it's a good idea to break out the bug spray (it's not). Let's explore a few common ant myths, and see what research has to say about them.
Ants don't (necessarily) mean your house is dirty.
The most common advice, when it comes to ants, is keeping things clean. And it's true that leaving food out will attract ants, but even the cleanest houses get ants sometimes.
"Finding a few ants in your home doesn't mean your house is dirty," Tanya Latty, a professor at the University of Sydney, wrote in an article for The Conversation. "We simply live on a planet that is absolutely teeming with ants."
This isn't to say cleanliness isn't useful — just that it's not a guarantee. It's still a good idea to store food in airtight containers and clean hard-to-reach places like under the fridge and stove, according to Latty. But even the slightest amount of food can attract ants: "Ants have tiny stomachs, so even small crumbs or the residue from spilled sugary drinks can be enough to entice them back," Latty wrote.
Food isn't the only reason ants come inside. They may be looking for water, meaning even small plumbing leaks could attract them, or seeking somewhere dry to live after heavy rain. Cleanliness is only one factor. Another thing you can do, according to Latty, is seal any small cracks or other potential entrances.
Bug spray isn't the best idea
You might, after seeing a line of ants in your house, reach for a can of bug spray. And it will kill the ants you can see, granted, but the ants you can see aren't the problem.
"Ant poison may make you feel like you're accomplishing something, but you're not," Michael Hansen, PhD, a biologist and ecologist, wrote in an article published by Consumer Reports. "Unless you solve the problem of what's attracting them to your house, and how they're getting in, you should remember that there are thousands of ants in every colony, and you'll just keep seeing them."
Bug spray also has downsides beyond simply not working, according to Hansen. "Some of these sprays contain chemicals that are endocrine-disrupting compounds, which can alter our hormones," he said, adding that similar compounds have been linked to effects on children's development, even at the low levels you'd be exposed to when spraying your house.
Instead, purpose-made ant baits are a better option. Unlike spray, which only affects the ants you can see, bait is carried back to the colony by worker ants and eaten by the rest of the group, killing it at the source. Different species are attracted to different baits, so you may need to try a few.
Pepper and cinnamon can deter ants, but not for long
So bug sprays are out, but what about natural remedies like cinnamon or pepper? The idea is that a strong smell can disrupt the trail ants use to navigate. There's research to back this up: a study by researchers in Malaysia found that extracts of chilli pepper, black pepper, and cinnamon all deter ants.
You could use any of these remedies to break up the chemical trail ants rely on, without the health concerns tied to bug spray, and you might notice they work for a while. But if ants are determined to get in, they'll eventually find another way. Research from Stanford University suggests ant colonies are extremely good at finding workarounds to broken trails, meaning this is only a short-term fix.
Again, you're probably better off sealing any entrances ants may be using, ensuring there's no food or water lying around, and setting out ant bait.