How to Keep your Rain Barrels Mosquito Free

Rain barrels are beneficial for the “Go GREEN” initiative as they help reduce the amounts of water that is being wasted for irrigation. However, along with this great environmental step in the right direction also comes the potential for a mosquito breeding ground.Today we are going to discuss how to keep your rain barrel from becoming a breeding ground and keep the area mosquito free.

When collecting rain water in a barrel system it can sit stagnant for days before you collect enough to use. These conditions are perfect for mosquitoes to lay their eggs in.

Don’t let mosquitoes take over your rain barrel! Make some modifications to keep your rain barrel mosquito free. Try one of these environmentally safe solutions to keep your water safe and plants happy.

Mosquito Free Rain Barrels

Well the first most effective and obvious solution would be to empty the rain barrel completely within five days of it filling up. Not only does this solution keep the rain barrel mosquito free but it will also reduce runoff. This is one of the rain barrels main purposes. While this option is the most obvious it is now always possible due to the length of time that it takes to collect enough water for use.

Add Mosquito Predators

Small goldfish or mosquitofish are natural predators that can be added to keep your rain barrel collection system mosquito free. These small fish prey love to snack on mosquito larvae. Just by adding one or two of these fish to each rain barrel you can keep mosquito larvae from maturing into pesky adults. I recommend checking with local conservation departments as some areas offer mosquitofish at no cost to help keep the mosquito population and threat of diseases down. Goldfish may require a bit of extra food to supplement their diet. Either way adding fish is a win-win situation: they will devour the mosquito larvae and their waste will be beneficial for your soil.

Create an Oil Slick

Providing the water level in your rain barrel can be kept above the output spouts, add a layer of oil (preferably food-grade) to the top of the water. The oil will float on the top of the water creating a film that suffocates the mosquito larvae leaving the water mosquito free! The oil will also act as a shield preventing any further mosquitoes from getting in and laying their eggs. Just add 1/4 c of food grade oil once a week after each storm. It is not suggested that you use this step in conjunction with the fish as the oil will prevent the water for becoming oxygenated and eventually kill off the fish.

Drop in Mosquito Dunks

Dropping in one Mosquito Dunk each month will keep your rain barrels mosquito free. Mosquito Dunks are made of Bacillus thuringiensis israelensis or Bti, a bacteria that kills mosquito larvae (as well as black flies). The dunks will slowly dissolve over time releasing the bacteria for continuous control. The Mosquito Dunks are designed to treat stagnant water in ponds, rain barrels, bird baths and more. They are not harmful to plants or pets.

Cover Intake with Fine Mesh

If you do not want to add anything to the water to keep it mosquito free you can cover the intake hole with a fine mesh. This will prevent adult mosquitoes from being able to enter the barrel. If mesh is not available use a pair of nylon pantyhose, this should do the trick. The mesh or pantyhose will keep mosquitoes from infesting but allow the water to enter the intake hole for collection. The downside of this method is that it will need to be checked often to ensure that they are not breaking down or that any holes are producing. Even the smallest hole can become an access point for mosquitoes.

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