Killing Roaches Outside with Spray Insecticide and Granular Bait
Some roach species aren’t just problems inside the house but outside, too. Luckily, insecticide sprays and granular baits make it easy to create a pest-free perimeter around your home.
We’ll show you how to measure and mix insecticide products, apply them with a sprayer and spread granular bait in some key areas.
- Transport Mikron Liquid Insecticide (1 quart)
- Maxforce Complete Granular Bait (4 lbs)
- Sturdy rake or broom (optional)
- Chapin 1 Gallon Pump Sprayer
- Solo 421-S Portable Spreader (optional)
- Plastic jug or container
- Protective glasses
- Disposable gloves
A. Find Cockroach Entry Points
Before you start, it’s important to identify exactly how
cockroaches are getting in and where their entry points are. For more on this
step, see our printable Roach-Free Recipe for finding roaches.
Then, take a few minutes to rake or sweep any leaves, twigs or other debris
away from areas you’re going to treat.
B. Purchase Supplies and Read Product Labels
- Purchase a 1-gallon spray tank. Liquid insecticide needs to be diluted with plenty of water for spraying.
- Purchase a package of disposable gloves and a pair of safety glasses.
- Read all instructions and warnings on product labels before using an insecticide or bait.
C. Mix the Insecticide Spray
- Start by filling your spray tank about halfway with water.
- Measure the appropriate amount of insecticide (usually 1/2–1 oz) according to the label.
- If the bottle features a squeeze-and-pour mechanism, remove the cap and seal from the side with the small compartment and gently squeeze until the liquid reaches the appropriate measurement mark.
- If the bottle features a tip-and-pour mechanism, tip the bottle slowly so that the liquid pours from the large compartment into the small compartment. Then, tip it back so the right amount remains in the measuring compartment.
- Add the insecticide to the spray tank. Continue filling the spray tank with water until you reach its fill line (or the required amount).
D. Use the Sprayer to Apply the Insecticide
- Pressurize the sprayer by pumping the handle repeatedly.
- Hold the trigger on the wand to activate the sprayer.
- The Chapin sprayer also has a locking mechanism to enable a continuous spray.
- Simply carry the tank by the handle in one hand and aim the hose with the other.
- Twist the nozzle to adjust between a narrow and wide spray.
E. Where to Apply Insecticide Spray
- It’s important to spray all of the target locations you identified in the first step.
- Treat air conditioning lines, pipes and wires thoroughly.
- Also, spray around any bathroom, stove or laundry vents near the ground. Turn the nozzle upside down to reach beneath those that stick out from the wall.
- Treat all cracks and crevices in the ground or foundation around your home.
- Spray window and door frames that might be worn or cracked.
- Apply the insecticide to the mulch or stone along exterior walls and gutters where leaves and debris tend to gather.
F. How to Apply Granular Roach Bait
- If applying by hand, use a plastic scoop (or wear durable, disposable gloves) to sprinkle the granules in wide arcs around the perimeter of your house. Some ice melt shakers will work, too.
- Walk slowly all the way around your home, spreading granules evenly in the mulch, soil and grass along walls.
- Treat fence lines, crevices in pavements, flower beds and the areas around your garage or shed.
- If you’re treating a large area of land, use a spreader (handheld or on wheels) to apply the granules evenly.
- If you apply around sidewalks or other nonporous surfaces, sweep the granules into the grass or soil after you’ve finished spreading.
- Apply extra granules to high-risk areas, including flower beds, sprinkler valves and hose bibbs.
- If your bait recommends wetting the granules after spreading, just fill your sprayer from before with clean water and lightly wet the areas you’ve treated.
Further reading: Kill Indoor Roaches with Insecticidal Dust
Don’t let pets play in areas you’ve treated with spray or
granules until after the product label’s recommended waiting period.
Some homeowners report seeing dead roaches after only 3 days
but it could take multiple applications for bait to completely eliminate an
infestation. Don’t apply granular bait in areas where it could wash into
reservoirs or streams. Don’t use a hose to wet bait because it could cause