To kill bugs in houseplants, use a garlic based spray, garlic cloves or a commercial pesticide treatment consistently until the pests are eliminated. Proper watering techniques and preventative measures are necessary to completely eradicate the insects.
To eliminate aphids and mites living in houseplant soil, mix a teaspoon of freshly squeezed garlic juice with a teaspoon of rubbing alcohol, then pour the mixture into 12 cups of water. Pour the solution into a spray bottle, and spray the plant and top layer of soil thoroughly. A whole clove of garlic can be placed in the soil to help deter and prevent pests. Spider mites can be eliminated by mixing 1/4 cup of buttermilk with a cup of flour and a gallon of water, and then misting the plant with the mixture.
A mixture of 4 cups of water, 4 tablespoons of starch and a few drops of liquid dish detergent eliminates infestations of white flies, aphids and thripes. Allow the mixture to remain on the plant for several days, then gently spray the plant with water to remove the mixture. Repeat the treatment process as needed until the soil is pest-free.
Insecticides, such as neem oil, can be used to kill pests living in houseplants. Apply the product according to the directions on the package, and choose a product that is designed for indoor use. Avoid over-watering plants to prevent pest infestations after the insects are eliminated.