Monday, August 10 · 6 min read
The mosquitoes biting you in your own back yard almost certainly hatched in your own back yard. They didn't drift in from a marsh three miles away.
Below: why they picked your place, the nine containers to empty this evening, which repellents hold up and which are theater, the $26 that handles the water you can't drain, and the free trick that clears a patio.
Reply and tell us where they get you worst, we read every one.
Why Mosquitoes Pick Your Yard
The mosquitoes that bother people in suburban yards are mostly container breeders. They lay in small, still volumes of water near where they live, and many of them spend their entire lives within a few hundred feet of the spot they hatched.
You can use this to your advantage! Why? Because the population biting you on your patio is, to a large degree, a population you are hosting.
TLDR: Yard mosquitoes breed in small containers of standing water and don't travel far. Emptying the water near your house does more than anything you can spray.
The mosquitos don’t need much water; far less than you’d expect, actually. Some species will complete a life cycle in as little as a bottle cap's worth, and in August heat the run from egg to biting adult only takes about a week to ten days. That means a weekly pass through the yard breaks the cycle before any of them finish.
Why they find you specifically is also very simple: you're a CO2 plume. Every breath you exhale puts out carbon dioxide, and mosquitoes track that plume upwind from a surprising distance, closing in on body heat and the compounds on your skin as they get near. Nothing about your blood type or your diet is doing the work here.
Fortunately for you, most yard mosquitoes are poor fliers. They cruise slowly and they operate low, which is why a patio can be miserable while the lawn ten feet away is fine, and it's also the basis of the free fix at the bottom of this email.
Species will differ on when they’re most active. Plenty of them peak at dawn and dusk, but some of the container breeders will happily bite you at noon in the shade. If you're getting hit at odd hours, that's normal.
So the order of operations is to drain water first, then get some personal protection, then everything else. The water you can't drain has a $26 answer further down.
The Nine Things in Your Yard Holding Water
Take a bucket and walk the perimeter of your yard, and while you do so, keep your eyes peeled for:
Plant pot saucers. The single most common breeding site around a house. Tip every one, and consider going without them outdoors.
Gutters. A gutter with a blockage holds a long, still puddle you can't see from the ground. This is the one people never check.
Tarps and covers. Grill covers, furniture covers, boat and trailer covers. The crease holds water for weeks. Pull them taut or fold them away.
Bird baths. Keep it, but change the water every few days. Moving or refreshed water doesn't support larvae.
Kids' toys and sandbox lids. Wagons, buckets, upturned lids, the little slide with a dip in it.
Buckets, wheelbarrows and watering cans. Store everything upside down. That single habit removes a whole category permanently.
Corrugated downspout extensions. The ribs hold water even when the pipe looks empty. Straight smooth pipe is better if you're replacing.
Old tires. If there's a tire anywhere on the property, it's holding water and it's breeding.
Condensate pans and rain barrels. The tray under an AC unit, and any barrel without a fine mesh screen over the inlet.
Then set a recurring reminder for a weekly lap. Since mosquitos mature in around a week to ten days, a weekly pass means nothing that hatches in your yard reaches the biting stage.
One habit worth changing while you're out there: water the lawn deeply and early in the morning rather than lightly every evening. Evening watering leaves puddles sitting overnight in exactly the conditions mosquitoes want, and it costs you more water for a worse lawn.
The Handbook: What Repels Mosquitoes and What’s Just Marketing Hype
The active ingredient is the only thing you should care about. Everything else on the shelf is packaging.
The ones with real evidence behind them. EPA-registered actives are the shortlist: DEET, picaridin, and oil of lemon eucalyptus (the refined version, listed as PMD). Picaridin is the one worth knowing about if you've written off repellent because you hate DEET, since it doesn't have the smell and doesn't melt plastics. Duration scales with concentration, so read the percentage rather than the marketing on the front.
Where it goes. Repellent belongs on skin and on clothing, applied thinly and evenly. The missed spots are ankles and the backs of hands, which is where most bites land.
The ones that underperform. Citronella candles produce a small, easily disturbed zone that any breeze removes. Wearable wristbands and clip-on badges protect a few inches around themselves and leave the rest of you exposed. Ultrasonic phone apps have no supporting evidence at all.
Bug zappers are mostly destructive. The light attracts night-flying insects broadly, and studies of trap contents have consistently found mosquitoes make up a tiny share of the kill, while beneficial insects make up most of it. You're running a light that kills moths and beetles in a yard you'd rather have them in.
Area repellers sit in between. The devices that heat a metofluthrin or allethrin pad do create a real zone, and they work best on a still evening in a defined space like a deck. Wind moves the zone somewhere else, which is a fair thing to know before you spend.
If you buy one thing in this category, buy a repellent with a named active ingredient and a percentage on the label.
The Smart Buy: The $26 That Handles the Water You Can't Drain
Some standing water can't be emptied. A pond, a rain barrel you actually use, a low corner that holds runoff for days, a neighbor's ditch you're downwind of. That's what larvicide is for, and the one we'd point you to is a pack of BTI dunks, 20 for $25.99.
BTI is Bacillus Thuringiensis Israelensis, a naturally occurring soil bacterium. Larvae feed on it and die. The dunk releases bacterium for 30 days or more, and one covers about 100 square feet of water surface regardless of depth. Summit, who make them, state they're harmless to plants, fish, frogs, turtles and beneficial insects, and the product is approved for organic production.
Why we'd point at the 20 pack rather than the two or six packs at the hardware store is pretty simple: per dunk it's dramatically cheaper, and they store indefinitely in a dry place. Realistically, you’re going to be using them rather frequently too, so bulk is better.
Keep in mind: BTI kills larvae, not adults. Put a dunk in your pond today and the mosquitoes biting you tonight are unaffected, because they already hatched. It takes a couple of weeks to show up as fewer bites, and it does nothing at all about mosquitoes breeding two doors down. It's the right tool for water you're keeping, and no substitute for the bucket walk above.
Affiliate note: The Home Wire may earn a commission if you buy through our link, at no extra cost to you.
Steal This: Point a Fan at the Patio
If you own a floor fan, you own the most effective patio mosquito control there is, and it costs nothing to find out.
Yard mosquitoes are slow, low fliers. A moderate breeze is hard for them to fly against, so a fan on the deck creates a zone they struggle to enter and can't hold position in. It works on the same principle as sitting somewhere windy.
It does a second job at the same time. That carbon dioxide plume coming off you is what they home in on, and a fan shreds it, so you're both harder to reach and harder to find.
Set it low and aimed across the seating area rather than up at people, roughly at ankle to knee height, because that's the altitude they work at. Two smaller fans at either end of a long deck beat one big one in the middle.
The nice part is that it needs no chemicals, no refills, and nothing you have to remember to buy. It also cools everyone down, which in August is not the worst side effect.
One quick tap: how bad are they where you are?
How bad are the mosquitoes where you are?
That's why they picked your yard, the nine containers to tip out tonight, what to actually put on your skin, the dunks for water you're keeping, and the fan that clears a deck for free.
Reply and tell us where they get you worst, or forward this to whoever keeps buying citronella candles. See you Wednesday.
The Home Wire
Affiliate disclosure: The Home Wire earns a commission on some links in this email, at no extra cost to you. We only recommend products we believe earn their place in your home.
This is a marketing email from The Home Wire. {{address_text}}. You're receiving this because you signed up for The Home Wire. Unsubscribe and Manage preferences, one click, no questions asked.