While some insects may prove beneficial to a garden's health, other insects may devour and kill whatever lies in the garden. Some insects may also bite humans or pets, leading to infections. While some home remedies can resolve an insect problem, the citrus fruit lime will likely not prevent the problem. However, other compounds, such as hydrated lime, can relieve humans, pets and plants of many insects.

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The sugar content in limes can attract insects.

Hydrated Lime or Dolomitic Limestone

Dolomitic quicklime, or dolomitic limestone, contains high quantities of magnesium carbonate. Dashing hydrated lime -- a powdered compound composed of water and calcium oxide -- or dolomitic limestone around the soil will kill and repel soft-bodied critters like snails or slugs. Put a little of these lime products on plants to offer added protection against fungus. Read the labels on any products you purchase regarding how frequently the product should be used. Use only the amount indicated on the package to avoid harming plants, soil, pets and people.

Citric Acid

Citrus fruits such as lemons and oranges can prove beneficial in the battle against garden intruders. Crush the fruits of both lemons and oranges and mix into hot water. This remedy, along with boiling water mixed with garlic products, can prove effective against fire ants -- aggressive ants that can bite and sting -- termites and similar pests. Pour these solutions over the nest to kill and repel the ants and other pests. Avoid overuse, as these products can make the soil too acidic for plants.

Alcohol

Pull the liquor, wine, beer and other alcohol from your cupboards to create a natural remedy against insects. Avoid alcohols such as rubbing alcohol. Mix up to a few tablespoons of alcohol into a gallon of water. Like dolomitic limestone or hydrated lime, a solution of alcohol and water will kill and repel soft-bodied insects like slugs or snails. Do not use more than a few tablespoons of alcohol per gallon of water, as the solution could also kill plants.

Other Repellents

Start growing plants such as basil, bay leaf, lavender, rosemary, sweet woodruff or tansy to repel pests such as flies, mosquitoes, ants, beetles and moths. Arrange these plants close to other plants to keep insects away. Spreading dried spices derived from those plants in the garden, around the patio or in the home can also repel the insects. Grow plants in pots to easily move them about the garden to protect other plants.