I have an ongoing issue with grain weevils in my home. Found a bag of old infested wheat pasta and threw it away but that was months ago. Now we have an empty cupboard and pantry but still we find them in the kitchen and living room. What can I do?
Grain weevils will feed on a range of products including pasta, bread and flour. Typically some are brought home from the grocer and never noticed. But if something is stored for awhile, it can allow feeding larvae to pupate and emerge as adults. Once this happens, you’ll start seeing them foraging throughout the home.
The adults aren’t smart nor are they good at finding good places to lay eggs. Once mated, females will lay eggs most anywhere. If your cupboards are bare, well, they’ll no doubt be on the move most anywhere.
At this point you need to do a thorough treatment meaning all rooms should be sprayed. Remember, just one adult female can lay many eggs and if the hatching larvae find anything good to eat, they’ll survive. This can happen in furniture, carpeting and even bedding. Larvae don’t need much food to grow and can find whats needed in carpets, under couch cushions, etc. easily.
Once they get their full, they’ll spin a cocoon and pupate. In a month or two they’ll emerge as the adults you’re seeing and no doubt this is what you have happening right now.
To end the problem, you’ll first want to treat every baseboard, carpet and bottom side of furniture with BITHOR and GENTROL. The Bithor is odorless and will control a wide range of pantry pests like weevils. Weevils are in the beetle family and as such, following the same life cycle. This means you’ll first want to kill the adults and then have an agent working to defeat hatching eggs which might not emerge for months.
Bithor and Gentrol will do both. The Bithor is fast acting and will kill active adults. This will stop new eggs. Add 1 oz to a gallon of water and plan on getting about 1,000 sq/ft of coverage per gallon of mixed spray.
Add 1 oz of GENTROL to the same mix with the Bithor. Gentrol is nothing but a protein. It won’t affect adults but it lasts a lot longer and will impact hatching larvae by preventing them from becoming reproducing adults.
Use a good PUMP SPRAYER to make the application and be thorough. This means treating all carpets, under furniture, baseboards, place mats and pantries. Plan on using 1 gallon of mixed solution for every 1,000 sq/ft of area and retreat in 2 weeks. After that the problem should be gone as the Gentrol will take over and kill off developing young hatching from eggs 1-2 months following your second application.
If you have a lot of cracks and crevices to treat, especially in pantries or cupboards, use FS MP AEROSOL. This can comes with a straw injector making it well suited for treating these spaces. Larvae are known to crawl into the tightest of spaces and liquids alone will not often get to where they might be hiding.
FS MP has strong penetrating oils that can impact all stages of these weevils. And it will penetrate way deeper compared to the water based spray.
Like the liquid spray, plan on treating at least twice. If needed spot treat more frequently – especially if you find pockets of weevils in areas not well treated before.