Ants - a deterent

Most ants are beneficial, killing real pests such as fleas and bedbugs, but that's no consolation when they start streaming in under your doors and crowding your kitchen cabinets. Ants come inside because they're attracted to your food, but you can also use food to repel them; for example, one of the best ways to kill ants is by spraying them with lemon or peppermint-flavored water. If these lightweight measures don't do the trick, you might have to declare war by using bait traps and chemical insecticides.
Method 1 of 4: Deterring ants from wanting to enter the home
The best way to get rid of a house pest is to prevent it from even considering your home an easy target. Hence, deterrence is a prime focus for every homeowner potentially susceptible to an ant invasion.

Get Rid of Ants
1 Barricade your home. Since ants are tiny, they can find thousands of tiny doorways into your residence. Some of these are easy to identify, while others will only be discovered when there's a parade of ants marching through the chosen ant doorway.

2 Use caulk. Seal windows, doors and any cracks the ants crawl through with caulk. An additional benefit of doing this is better temperature control and lower energy bills. Plus, it's one of the least risky methods when kids or pets are involved.

3 Line suspected entryways with deterrent substances.
Salt and talc can be spread under doors, near windows and walls with better conscience. Tailor's chalk and baby powder usually contain talc and can be used to create a barrier for ants. Regardless of which form of talc you use, keep in mind that there are concerns about the potential carcinogenicity of talc, if you breathe it in––wear a barrier mask.

4 Apply scents and substances that ants don't like. Vinegar, peppermint oil, cinnamon, black pepper, cayenne pepper, whole cloves, and bay leaves are all examples that have varying claims of success. However, some of these might be harmful to pets and irritants to curious children. So ear this in mind

5 Create a landscape buffer. Ants often enter homes through nearby shrubs, vegetation, or overhanging trees. To eliminate this problem, create a dry, plant-free border by trimming or getting rid of overhanging trees, cutting back vegetation that is touching your home, and laying down a perimeter of gravel or rock
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Killing ants is sometimes a necessity when you have an infestation and there is no end in sight. It's the least desirable option but it must be considered when you have them in the home constantly.

1 Consider going from least harmful to most harmful approach first. Not only is this better for your health but it's also kinder for the environment.

2 Kill off the ant trail. A line of ants can be dealt with effectively and quickly so as to kill those in the line and deter any others from continuing to follow the trail. It is recommended to begin with locating the entry point first and creating a barrier straight away, such as a line of petroleum jelly, upturned duct tape or talc, so that the ants outside stop using the entryway. Then, try one of the following methods to deal with the ant trail:
Dip a sponge into soapy water. Simply wipe the sponge down the trail, collecting ants. Rinse them down the drain. Rinse and repeat as often as required until all ants in the trail have been removed.
Spray the trail with all-purpose cleaner or a bleach solution. Wipe it up with a wet paper towel. Spraying the nest can be effective, but you really want to make sure you get them all, otherwise killing part of the colony can simply encourage certain species to establish new colonies, which is counter-productive to you.


3 Squish the scouts. Colonies regularly send out lone ants to check for food sources. If you see an individual ant strolling across your coffee table, don't let it make it back to the nest alive. It'll tell the colony where you SPILLED the apple juice. If the scout made it back to the nest and brought back some friends, they'll be following a scent trail, single file. Unless you're ready to bait them, kill them all quickly.

4 Root out the ants already well entrenched in your pantry or other cupboard space. You'll need to use an attractive poison bait to get the ants scurrying home with new "treats" from their food hunting missions. Mixing boric acid powder or borax with water and sugar is the most common bait. Boric acid affects ants both externally (when in powder form; similar to diatomaceous earth) and internally (when ingested). Make a mixture of 1 cup water, 2 cups sugar, 2 tablespoons boric acid.
Wait for the ants to show up. Don't lure new ants with the bait because you could attract new colonies. Once there's a trail, place the bait next to it (not on it, or else you'll interrupt their march home). You can also place it in a safe part of the pantry where ants appear to be congregating.
If you have pets and/or children around (see Warnings below) use the bait in a jam jar where ants can go to seek "food". Screw the lid tightly and seal with adhesive tape. Pierce the lid with two or three small holes large enough for ants, and smear the outside with a little bit of non-poisoned bait to advertise the contents for ants. If you're concerned about the jar getting knocked over and the poisoned bait spilling out, loosely pack the inside above the bait with cotton balls.
You can mix peanut butter as well. Ants' cravings vary depending on the needs of the colony (sometimes they want sweets, sometimes they want something oily), so providing both will increase the likelihood that they'll take the bait. Once they've had their fill, remove all bait which may lose its poison when weathered, but still attract ants. You don't want to attract a neighboring colony.

5 Consider using a borax bait made at home. Use 1 tablespoon of peanut butter, 2 tablespoons of sugar, 2 teaspoons of borax, 1 teaspoon of water. Mix well. Place a small amount on little pieces of cardboard where the ants are active. Watch them swarm it and carry back to nest.
If it kills them too quickly, try 1 1/2 teaspoons of borax. You want them too carry it back and kill the colony and the queen.

6 Vacuum up the ants. Sprinkle and vacuum a little talcum powder or diatomaceous earth to finish them off in the vac and in the trash where you dispose of it. This second step is important to make sure that you don't provide the ants a new home inside your vacuum cleaner.

7 Make a mixture of rubbing alcohol, dish soap and water. Get a spray bottle, making sure to wash it out very well, and place about a teaspoon of rubbing alcohol and about a teaspoon and a half of dish soap. Then fill the spray bottle with water about an inch (2.5cm) away from the top and close it up tight. Shake the solution until bubbles start to appear and then you're ready to spray! Because of the alcohol in the solution, the ants will stay clear away from it.

8 Get a "Deep Reach" fumigator (aka "fogger"). These are reported to kill ants for 6 to 8 months, with the downside being that you may have to stay out of the place you fumigate for anywhere from a few hours to a few days. Search online for product reviews and inquire at local home improvement stores. Make sure you know the volume of the place you need to fumigate. If you're concerned about the use of potentially harmful chemicals in the home environment, this is not the approach for you and should not be used, if you have children, whose immune systems are still developing.

This is the least recommended option––ants have an important place in the ecology of your garden and general ecological health––they destroy a good many garden pests. Removing all ants completely can disturb the delicate balance, let alone deranging the "live and let live" stewardship human beings would do well to live by. However, should ants seek food or take up residence in play areas of your yard or inside your home, you'll need to remove them. Here are some suggested methods.

1 Locate the nest or ant hill. If you can find the source, carefully dig/puncture the soil and dump several gallons of boiling water into the nest. That should take care of the entire colony.

2 Try a homemade solution. Mix one part camphor oil with 9 parts denatured alcohol (ethyl alcohol that has a chemical added to stop humans from enjoying it), may be methylated spirits containing poison non-drinking alcohol. Pour over the ant hill.

3 Kill the queen. The best way to get rid of ants is to destroy their source: the ant queen. She produces a large number of ants and killing her will exterminate them; if you can, find and kill the queen inside the ant nest. She's rather shy and will hide in the bottom. This method is not recommended, if the ants are aggressive and/or sting.

Do your bit to discourage ant re-entry by keeping the house FREE of ant attractants. Cleaning up food and other attractive residues is an important part of getting rid of ants from the home and keeping them out.

1 Put food in airtight containers. This also has the added BONUS of keeping your food fresher. Also, should bugs that come in egg form in the foodstuffs hatch, they're caught inside the container, making their disposal easy and preventing their spread through the entire pantry. It's definitely worth the initial outlay on good storage containers.

2 Wipe down all surfaces. Tables and countertops should be regularly sprayed and cleaned with a mild bleach or vinegar solution.

3 Keep on top of your regular cleaning regimen. Sweep, mop, and vacuum regularly.

4 Keep the sink clean. Avoid leaving dirty dishes and standing water for ants to drink and do not put food in the drain. Remove all in-sink disposal scraps as soon as added.

5 Put pet food bowls in a slightly larger bowl. Add some water to the larger bowl, creating a moat around the pet food that the ants can't easily cross. Refill regularly.

good luck

personally i have used a mix of ant powder water and sugar - well mixed and placed near the trail (beware of pets and childrens areas) and believe me it works  - they take it back to the nest and kills them all in a matter fo days.