Natural Insecticides to Keep Fall Bugs Out

hands cleaning plant leaves with spray
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Fall is in the air, so rodents, spiders, wildlife, and insects are on the move. It’s time to relocate and snuggle in for winter. Many animals will take the opportunity to move inside your home to find a cozy habitat.

If you want to keep them away without dousing your home in toxic chemicals, you can make or find insecticides that do the job with natural ingredients instead.

Know what to look for, understand how bugs and spiders act, and find a solution for the invasion before your unwelcome visitors become a major issue.

Kinds of Common Household Bugs

There are countless types of bugs, and most of them aren’t on the holiday invite list. Insects can destroy crops, lawns, landscapes, and houseplants. They are annoying, irritating, and unwelcome. They can also bring illness, delivered right inside your home.

If you’re seeing bugs, you obviously know they’re there. Fruit flies congregate in the kitchen. Houseflies show up everywhere, especially when there’s food in the open. Stink Bugs blanket the side of the home and enter through any crack available.

Silverfish and earwigs hide out in your closet. Moths take up residence along the ceiling. Fleas begin bothering the animals and humans alike. The thought of bed bugs might also keep you up at night.

Some bugs remain discrete, hiding in the dark corners of closets or multiplying in the basement. Cockroaches and beetles might keep to themselves.

Spiders are also lurking about. You may see an empty web or many webs with trapped prey woven into the design.

Very small bugs, such as aphids, may also find a host in your houseplants, causing discoloration, falling leaves, spots, or drooping branches.

aphids on plant

Prep Plants for Winter

A big part of keeping insects and spiders at bay is taking preventative action. Make sure your plants are healthy and disease free before the stresses of winter don. Take care of replantings, putting plants in nutrient-rich soil. Remove dead leaves and branches.

Give your plants a shower in the bathtub, sink, or outdoors. Also provide a final fall feeding.

If you notice bugs or evidence of bugs, such as holes in leaves, treat them immediately. Flip over leaves and look at the back side when handling plants. This is where insects often hang out. You may also find them in the soil.

Household Preventative Measures

One way to avoid using insecticides is to limit access so insects can’t get into the home in the first place.

Fill all holes around doors and windows through the use of insulation strips or caulking. If you see light from outdoors through any space, it’s an open freeway for bugs and spiders to move in.

Walk the outside of the home. Patch holes, fill gaps in the siding, repair cracks in the foundation, cover vents, and recaulk windows and doors as needed.

Repair holes in window and door screens. Also double check areas where plumbing pipes or electrical cords enter the home and fill any gaps around those.

Pressure wash the home from top to bottom in order to remove webs and blast insects out from behind siding and other hiding places.

Also outside, hang flypaper and use bug zappers to eliminate them before they find their way inside.

Match the Insecticide to the Plant

When evaluating which insecticide to use on plants, do a bit of research to make sure it won’t hurt the plant you’re applying it to. Target a leaf or a cluster of leaves. Apply the spray and allow it to set for 24 hours. If you don’t see any adverse effects, apply to the rest of the plant.

Soap and Water

The first line of defense against nearly every type of bug is a simple combination of soap and water. Use a natural soap such as the well-respected Dr. Bronner’s.

Combine one gallon of warm water with 2 1/2 tablespoons of pure-castile liquid soap. You can apply using a small squirt bottle or a sprayer.

Soap sprays can also be found online and in gardening centers.

Protect surfaces around where you’re spraying by putting down plastic or thick blankets. Although it’s natural, the soapy mixture can discolor and leave water marks on wood.

It’s best to take plants outside or spray them in the bathtub or a work station sink.

If you’re treating bugs that are not on plants, use caution when you spray. Try to catch them outside the house as a first line of defense. For example, when you see a stink bug convention taking place, spray them directly.

Soapy water only works when you apply it directly to live bugs. It’s not a good preventative measure or a deterrent.

Once you’ve applied it to leaves or bugs directly, check the situation in 24 hours and reapply if necessary.

White Vinegar

white vinegar in dish

While the smell of white vinegar may not be all that appealing to you, it’s very offensive to many bugs. Create a 50/50 mixture of white vinegar and water. Spray it anywhere there are problem pests.

Apple cider vinegar is very effective if you’re battling fruit flies. Simply place it in a shallow bowl with a few drops of dish soap. It can also be used to battle ants, spiders, and mosquitos.

Herbs and Spices

Bugs, rodents, and spiders all have things they dislike as much as we dislike them. More of a deterrent than a killer, there are many ingredients in your home already that will keep these pests away.

Liberally use cleaners with mint, citrus, lavender, and other strong scents. Vinegar does a nice job of deterring bugs too, but it may also be an unpleasant scent to you.

These same scents can be applied to cotton balls and tucked into drawers or cupboards.

In addition to scented cleaners you can rely on dried herbs such as mint or lavender, either in sprigs or tucked into sachets. Simply leave these springs in problem areas.

Pungent spices are also effective deterrents. Stop them at the door with a path of cinnamon, cloves, paprika, cayenne, cardamom, or other stand-out scent.

Serve a Beer

slug on a glass of beer

If you have a fall garden, you may be dealing with a non-insects pest--slugs. Slugs are an unwelcome guest to the garden party, happily chewing through all forms of plants. But get your guest a beer, served in a cut off plastic Solo cup or beer can.

The slugs will eagerly crawl into the pool of beer, but enjoy the lager so much that they are unable to get back out.

Grow Marigolds

This is an example of one plant working for the good of other plants. Marigolds are perhaps the most widely-recognized natural insect repellent in the gardening world. Plant them in pots around doorways or in window boxes. Insects won’t be tempted to bust past them in order to invade the house.

Bring in the Predators

Another type of plant actively removes insects--by eating them. Yes, they are real, and yes, they really eat bugs. Plus, they are interesting plants that inspire conversation. Examples include the commonly known Venus Flytrap, Cape Sundew, Spoonleaf Sundew, Butterwort, and Tropical Pitcher Plants.

Go Bananas

If aphids are an issue, invite a few friends to the party by introducing ladybugs that may look pretty, but will actually eat the aphids. As a backup, bury finely cut banana peels in the soil beneath the plants to deter aphids from getting too homey on your leaves.

This hack is better outside the house, but when aphids get inside, make a tonic from the banana peels instead. Commonly called banana tea, you can make it by soaking banana peels in water for several days. Then strain the liquid and place it in a spray bottle. Apply it directly to the aphids.

Give a Dose of Diatomaceous Earth

diatomaceous earth on wood spoon and blue surface

Diatomaceous Earth (DE) is a food-grade product that kills pretty much every kind of crawling insect with a shell. Sourced from finely ground fossils, DE particles contain jagged, sharp edges that kill the insects when they move through it.

Sprinkle DE anywhere you’ve seen bugs that move across the ground in your home. Remember to target dark, damp spaces such as under sinks, in cupboards, and along baseboards. Leave the powder in a place for a day and then vacuum it up.

Neem Oil

If you’ve ever Googled natural insecticides, neem oil was likely at the top of the list. That’s because it’s incredibly effective against a wide variety of insects, yet doesn’t harm beneficial insects such as ladybugs and butterflies.

Since it is an oil, it basically suffocates leaf eating insects like cabbage worms, squash bugs, nematodes, and grubs. Neem oil is easy to find in any garden center or online. However, it can require repeat applications to be effective.

One more advantage worth noting is that bugs rarely build up a resistance to neem oil, unlike most pesticides.

You can make your own oil spray by combining one cup vegetable oil with a tablespoon of liquid soap. Hold onto your mixture. When you’re ready for application, mix two teaspoons of the mixture with one quart of water and apply directly.

Tomato Leaf Insecticide

As your summer garden comes to a close, harvest some parts of the tomato plants before tossing them into the compost pile. Tomato leaf insecticide is most effective against aphids. To make it, chop up a few cups of fresh tomato leaves and steep them in a quart jar in room temperature water overnight.

Then strain the liquid and apply it with the use of a spray bottle.

Chili Pepper Spray

As we mentioned, most bugs don’t like spicy scents. Turn your spray bottle into a weapon with chile pepper spray by mixing one tablespoon of chile powder or capsaicin with a quart of water. Add a few drops of dishwashing liquid or liquid soap to help the mixture adhere.

Shake the insecticide and spray as needed.

Caution: Be careful not to inhale the spray or allow it to come into contact with the skin. The pepper can burn the skin, eyes, and lungs.

Garlic Spray

Aphids, spiders, and beetles don’t like your garlic breath, and definitely don’t appreciate garlic spray. To make it, pulse a few bulbs of garlic in a food processor or mince them by hand. Add a bit of water and allow the blend to steep. Then combine it with ½ cup vegetable oil and a dash of liquid soap.

This works as an effective deterrent so you can apply it early in the season.

Natural vs Synthetic

Most natural insecticides are less potent than the synthetic options made with toxic chemicals. For that reason, you’ll need to be vigilant, applying natural insecticides more often throughout the season or year-round.

However, the benefits of using natural products undeniably outweigh the inconvenience of having to do so more frequently.

Most importantly, natural insecticides don’t pollute the air, soil, water, and food sources. Subsequently, they don’t cause health issues like cancer, low birth rate, and other associated ailments.

Remember there’s a food chain to consider too. If you poison plants or insects, the birds and other animals that eat those bugs or plants are then affected by the toxins. The same holds true for pollinators that feed on those same plants.

Be sure your approach to deterring and killing insects and spiders is targeted for the lowest impact on the ecosystem.

Start in the off Season

Perhaps the best way to battle bugs during the fall and winter is to minimize them in the spring and summer.

Take stink bugs, for example. They lay eggs from May through about August. That means there’s a full hatch of mature adults by the fall.

However, if you eliminate them when the eggs are preparing to hatch you’re way ahead of the curve.

The same holds true for fleas. Keep them under control all year, so you don’t have a breakout at an unexpected time. Similarly, you can equip your outdoor space to battle the bug population by learning How to Attract Insect-Eating Birds, Part 1, and How to Attract Insect-eating Birds, Part 2.