Home Remedy to Kill Mosquito Larvae

That flying, buzzing mosquito that pesters you when you're enjoying your yard starts off as a black, squiggling wormlike creature in garden ponds, birdbaths, fountains and other standing water. More than annoying, in some areas, mosquitoes transmit potentially fatal diseases including West Nile virus. Controlling flying mosquitoes starts with controlling the larvae. Break mosquitoes' life cycles by killing the larvae using home remedies, ranging from cultural control to household products.

Bird bath
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Empty out containers of stagnant water to help prevent mosquito problems.

Expose the Water's Surface

Calm, sheltered pools of water create the safe haven that mosquito larvae need to thrive. Cut back overhanging branches, use a net to collect and remove fallen leaves and other floating debris from ponds. Reduce the number of plants growing in and around ponds and other water features. Adding a fountain can also discourage mosquitoes from ponds.

Removing plants and organic debris eliminates the food the larvae need. It also exposes the water's surface to the elements. Mosquito larvae are fragile and require protective shelter. If the surface of the water is disturbed by wind and rain, mosquitoes won't lay their eggs on the water's surface and the larvae get tossed around and die.

Release Mosquito Fish

Add life and movement to a water feature with fish. Fish add interest to water features and also feed on mosquito larvae and adult mosquitoes that may come to rest on the surface of the water. The aptly named mosquito fish (Gambusia affinis) does well in water features like troughs and fountains and effectively eliminates larvae. For the best results, release one or two mosquito fish for every 20 square feet of water surface area. To prevent introducing invasive species into your area's natural waterways, only use this method in completely enclosed water gardens and check before using the fish that they're not considered invasive in your area. Some cities may provide these fish for free to help control mosquitoes.

Apply Dish Detergent

Dish detergent makes the water inhospitable to mosquito larvae and repels adult mosquitoes looking for a place to lay eggs. Approximately 2 drops of dish detergent for every 10 square feet of water surface area will work. Do not use detergent in ponds with fish or other aquatic creatures. To minimize harm to the soil or plants, only use dish detergent that has been labeled as "biocompatible" or "biodegradable." This option works best on still, quiet water features or rain barrels. Fountains and waterfalls will foam if you add detergent.

Use Vegetable Oil

Vegetable oil is safe for plants and nontoxic to animals that may try to drink the water, but it's lethal to mosquito larvae because it prevents the larvae from reaching the air at the surface of the water. Use a couple drops of vegetable oil per 10 square feet of water surface area. Cooking oil evaporates and will need to be reapplied once a week until mosquito larvae activity stops. Do not use oil in ponds with fish or aquatic wildlife.