Our rain barrel came with our favorite kind of price tag: free. It's not too fancy, but it does the trick. Last week, though, we got two inches of rain—and that barrel is half full of water and teeming with mosquito larvae, despite our best efforts at a net cover. How to get rid of them (and keep them from coming back)? Here are a few tips.
We posed the question to some of our favorite local gardening experts. First, they told us, prevent bugs in the rain barrel by employing a good lid with small netting. Window screening works well and can be purchased cheaply at any home improvement store.
If it's too late to try and keep them out, try a plant-, pet-, and beneficial insect-friendly pesticide that's commonly referred to as BT. Bacillus thuringiensis, which we're now using to combat leafminers and pillbugs that are waging war against our squash and bean plants, is a pesticide that targets garden pests but it safe for humans, pets, birds, and bees. You can drop about one quarter of a BT donut (available at nurseries) into your rain barrel to stave off mosquito populations. That said, be sure to only use BT for short periods of time to deal with pest populations, as completely eradicating nasty pests could potentially change your garden's natural biodiversity.
Related posts:
• How To Make a Rain Barrel
• Good Questions: Rain Barrel Alternative?
• How to Make a $25 Rain Barrel
(Image: Flickr member Ken_Mayer, licensed under Creative Commons.)
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I love that rain barrel picture! And that's for the tips, I've been wanting to make a rain barrel ASAP!
We've been looking for a non-plastic rain barrel. That one in the picture is beautiful. I am so envious that it was free. Any hints for finding free or cheap ones?
Would there be a possibility of adding a small solar charged fountain near the water line, (maybe on a floating base to adjust with the water level)?
I believe if the water surface is moving constantly, the bugs would be less inclined to lay eggs in it.
I love pyh's idea of installing a fountain on the barrel to prevent mosquitoes to lay eggs. That's genius!
I've always wondered about putting a goldfish or two in there - I guess it would depend on what the lowest water level your rain barrel sees is, and how warm that water gets.
@Emmi—sadly, this barrel is not mine (our free one is a white plastic barrel; not much to look at but hey! I'll take it!).. but agreed. It's lovely.
@pyh—I like this idea!
@John B—yes, keeping an eye on the temperature of the barrel is definitely important for the fishes' sake. But it would be great to have a natural ecosystem, and the fish poo would be good for the garden, to boot.
We had a half barrel and to keep mosquito larvae out we had a few goldfish. Unfortunately, the raccoons discovered and caught them all.
Don't use goldfish, they're not interested in the mosquito larvae. You want a (usually) gold-colored fish called a comet (often used in stock watering tanks for the same purpose). These guys are INDESTRUCTIBLE! My parents have some in their rain barrel that have been there for three years - including water levels of only a few inches and being frozen over winter. They do give them a sprinkle of food every other day to keep them happy - but that's all they need! If you go the fish route, make sure you let the clerk know what you hope to use the fish for so that they can point you in the correct direction.