Red Ant Infestation in a Vegetable Garden

Red ants are also known as fire ants; this is because of both their color and the pain inflicted upon the enemy. Red ants can destroy a garden, using it for a food source until it is depleted. Because of colony sizes, distances between mounds to food sources and their ability to move quickly red ants are often hard to control. There are various chemical and natural methods to eliminate colonies although all methods can take several days to show full effects.

Red ants are an invasive ant species. Colonies can reach 200,000 or more in number; the queen lays an average of 800 eggs per day according to Texas A&M University. Food for red ants consist of oil-containing seeds, seeds pods and other insects. The potential for a red ant colony to inflict pain is substantial because when a colony is attacked thousands of soldiers emerge in defense. Fire ants sting with venom similar to bees and have pincers to bite as well bringing potentially life threatening allergic symptoms to some people and pets.

While red ants live off of seeds found in gardens, they do not always live nearby or in the garden. Mounds can be up to 18 inches tall and be located up to 75 feet away from the vegetable garden. Colonies are often placed in dense cover such as weeds or surrounding high grass. A common sign that an ant colony is nearby is the existence of an aphid colony within the garden. Ants feed off of the secretions of aphids; because of this an ant colony will help build and protect an aphid colony within the same garden where ants gather seeds.

There are various chemical solutions to an ant infestation. Poisons containing spinosad and methoprene can be applied to the lawn and garden safely. These poisons create a contagious virus according to the extension service at Mississippi State University, which is spread through the colony as the ants return. Liquid drenches can be applied directly to a mound when used properly and with safe ingredients. Spinosad, permethrin and carbaryl are accepted poisons; acephate is not recommended as crop roots can absorb it.

There are natural solutions that also work to eliminate red ant colonies. Removing the aphid colony eliminates a large food supply. Spraying aphids with a hot soapy mixture will kill adult aphids; introducing predators such as ladybugs or lacewings also eliminates the colony as these insects eat aphids. Boiling water poured directly onto and into the mound will drive off or kill the colony. Boric acid is effective but should be avoided if there are children or pets in the household.

Because ants are attracted to garbage, high grass and weeds the best prevention is to contain the environment. Maintaining the garden, removing decaying or rotting plants and fruit, mowing the lawn and monitoring the garden are the best methods. Planting specific strong smelling plants will deter ants from the garden; mints, garlic and pennyroyal are examples. Spray the garden with lemon juice or hot pepper sprays because these contain acid.

References:

Mississippi State University Extension: Fire Ants in and Around Home Gardens

Texas A&M University Extension: Managing Fire Ants in Vegetable Gardens

Victoria County Master Gardener Association: Fire Ants Can Harm Vegetable Gardens