Ants can be an annoyance, whether they are indoors or in the garden. The ants don't eat your plants and can benefit the garden by eating the larvae of fleas and flies, helping to break down organic materials and aerating the soil. When ants live among your outdoor plants, it often indicates the presence of harmful insects, such as aphids, mealybugs or scale, which the ants cultivate for their sweet excretion. You might not be able to kill all of your ants with natural methods, but you can repel them to keep them away.
Killing Ants Without Poisons
Keep all outdoor areas clean to discourage ants from coming to your garden. Tightly seal garbage cans, keep spills cleaned up and remove pet food after your animal is finished eating.
Spray ants with a soap spray. You can purchase insecticidal soap at a garden supply store or make your own. Saturate affected plants well and repeat your application every other day until you see no further sign of ants. Also spray ant trails.
Make a natural ant killing bait by combining 1 tsp. of boric acid and about 1/3 cup of apple-mint jelly. Drop dabs of this every few feet along obvious ant trails. The jelly attracts the ants while the boric acid kills them. Repeat your application every few days when you begin to see your bait disappear.
Spread diatomaceous earth on the soil around affected plants. Because this natural product dissolves after it gets wet, spread more of it after a rain and after you water your garden.
Use cedar chips as mulch throughout the areas of your garden where you have noticed ants. This type of wood repels ants and other insects.
Sprinkle corn meal around ant nests. Ants will eat this grain but later will swell up and die when they drink water.
Grow plants that repel ants, such as spearmint, peppermint and sage.