West Nile disease and mosquitoes: Those words can send a chill up many a gardener’s spine – especially water gardening enthusiasts.
You may have concerns that your water feature, garden pond or birdbath could promote the breeding of mosquitoes and increase the risk of someone in your family contracting the disease.
Controlling mosquitoes in your water garden
It’s important to change the water in bird baths regularly
If you’ve done some reading on the subject, you’ll know that spraying adult mosquitoes is pretty futile. Prevention is the key.
The best way to keep mosquito numbers down and reduce the threat of West Nile disease is to clean up any areas wheremosquitoes can breed.
Mosquitoes need water, especially stagnant or still water that’s rich in organic matter for mosquito larvae to feed on. Unlike birds or other insects, mosquitoes don’t fly very far and tend to stay near the places where they hatched.
You can reduce local mosquito populations significantly by removing opportunities for them to breed, but getting rid of your pond, bird-bath or water feature is not the answer.
Safe water gardening tips
Garden ponds add valuable habitat to your backyard and encourage all kinds of beneficial creatures to take residence there.
A water feature will attract dragonflies, frogs and toads and birds and add lots of pleasure and interest of your garden.
So keep your ornamental pond, but follow these West Nile preventative measures:
Stock your pond with fish and aerate it
If you have fish in your pond or water garden, they will readily eat any mosquito eggs or larvae.
Pond aeration and/or filters keep the water moving so it won’t become stagnant. If your pond doesn’t have an electrical outlet nearby, look into solar-powered pond pumps and pond filters.
Use Bti mosquito dunks
Mosquito Dunks & Granules
Bt stands for Bacillus thuringiensis a naturally occurring bacterium. The “i” stands for israelensis, the specific form that kills mosquito larvae before they emerge from the water as biting adults.
Bti is available to gardeners as granules or floating mosquito dunks. The product is organic and safe for birds and fish, which can still eat the mosquito larvae without danger.
You can use Bti in garden ponds, water features or anywhere you have standing water on your property. Be sure to read and follow the instructions on the package as to how much to use and how long the product is effective.
Bti in Canada
Unfortunately, Bti is still a somewhat restricted product in Canada, meaning that, in most areas, only licensed applicators can buy and apply it. However, unlicensed rural landowners can use it for farm ponds that don’t connect to a natural water course.
The rules may vary from province to province. (For local information, check with the Ministry of Agriculture or the Ministry of the Environment in your province.)