How to Use Certan B402 for Wax Moth Control
Protecting stored beeswax comb from wax moths is a major task for beekeepers. Certan B402 is a biological Bt solution that helps prevent wax moth damage before it starts. While not designed to correct an active infestation, it can help prevent future damage. In this article, I’ll share how I use Certan B402 for wax moths, how to apply it and when.
Wax moths can cause serious damage to valuable drawn comb. If you need more information about the pest itself or protecting stored honey supers, I have detailed guides on those topics.
What is Certan B402?
Known among beekeeper circles as “Certan,” the product is sold today as B402 (Certan) in the United States and B401 (Certan) in other parts of the world where available.
This is not a chemical insecticide. Certan B402 is a biological control that contains a concentrated solution of Bacillus thuringiensis (Bt), subspecies aizawai.
This bacterium produces protein crystals that are toxic to wax moth larvae — but harmless to honey bees when the product is used according to label directions.
Years ago, Certan was a favorite tool for beekeepers, but it was off the market for a while.
Thankfully, Certan received approval from the EPA for use by beekeepers again and it is suitable for organic farming operations.
How it Works
Certan leaves a protective layer over the comb. As wax moth larvae begin to feed on the wax, their digestive system is disrupted by the toxins. This causes the moth larvae to stop feeding and die.
Because of the way Certan works, it is only effective against wax moths in the larval stage. It does not kill adult moths or eggs.
Clearly this is why it is viewed as a preventative and not a control for a hive already in trouble.
Formulation
Certan is sold as a concentrated liquid that must be diluted with water before use.
According to the manufacturer (Vita-Health), a 5 oz bottle of B402 will treat approximately 70–100 Langstroth brood frames, 150 medium frames, or 200 shallow frames.
But, of course this depends on how heavily you apply the product. I’ll show you the small-batch mixture I use below. Treatment solution should be used within 24 hours of mixing to maintain effectiveness.
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Applying B402 to Stored Comb
You don’t need any fancy supplies — just a few measuring tools, a good sprayer and a container with a lid.
Purchase the Certan B402 from a bee supplier or buy Certan online).
I am sharing with you MY method for using Certan B402 to protect wax comb. Other beekeepers may use different methods, so always read and follow the product label.
My honey frames have been removed from the extractor and cleaned of any honey residue by the bees — they are now dry. If I have any unused brood frames, I give them a spray too — why not?
We are going to make a small recipe. You can double it for larger amounts of solution.
Step by Step
1. Shake the Certan – If this is your first time opening the bottle-you will find a foil seal. Shake the product vigorously (it normally settles during storage). Then, remove the seal – you may need a knife or scissors.
2. Measure the Water – Use your measuring cup to put 2 cups of water in the pint jar. (To make 2 cups of spray, I use a pint jar with a lid.
3. Add the B402 – With a measuring spoon put approximately 4.8 (almost 5) teaspoons of B402 Certan into the jar of water. You don’t have to be precise – this is not rocket science. Just get it close.
4. Mix well – Place the lid on the jar and shake, shake, shake to completely mix the water and solution together.
5. Spray the comb – Pour your solution into a good quality spray bottle. Test your sprayer with water before adding the Bt mixture.
Cheaper sprayers will work but they are unreliable and may result in losing some of your product.
Lightly but thoroughly spray each side of the honeycomb in your frames. You want good coverage but do not try to fill the wax cells with water- just a nice mist over all the surface.
6. Let the comb dry – Then, place the sprayed frames of comb in the sun or any place with good air flow and allow them to dry completely.
Once dry, they are ready to store in whichever manner you choose- or use again in the hive.
Important: Not every Bt product is the same. Certan B402 contains Bacillus thuringiensis subspecies aizawai and is specifically labeled for use against wax moth larvae on stored honeycomb. Don’t assume a Bt product intended for garden or agricultural use is suitable for your bee equipment.
How Long Does Certan Last?
One application of Certan B402 is designed to protect stored comb during the storage season. If treated frames are put back into use and stored again later, apply a fresh treatment according to the current label directions.
Though I will confess that I don’t repeat the treatment each year and so far have not had a problem.
When to Use Certan
The most common time to apply Certan is after you complete the honey harvest for the season.
After extracting your honey, frames of comb are removed from the honey extractor, cleaned by the bees and allowed to dry — it is time to spray them before storage.
For best results, apply B402 before wax moth damage begins. In my experience, one application gives excellent protection throughout the storage season.
FAQs
Certan B402 contains Bacillus thuringiensis (Bt), subspecies aizawai. It is a biological control specifically formulated for use against wax moth larvae on stored honeycomb.
No. Bt products are made with different strains and are labeled for different uses. Use a product that is specifically labeled for treating stored honeycomb and always follow the product directions.
Yes. Properly treated and dried comb can be returned to the hive when needed. Follow the current B402 label directions for application and use.
No. B402 works when wax moth larvae feed on treated comb. It is intended as a preventative treatment rather than a way to kill adult moths or clean up a heavy infestation.
Final Thoughts
Using Certan B402 is an easy way to protect valuable drawn comb from wax moth damage while it is in storage. I like that it is simple to mix and apply — and once the frames are dry, they are ready to store until needed.
For me, preventing damage is much easier than dealing with a stack of ruined comb later.Don’t let your stored comb be destroyed by moth eggs that may be there – even if you don’t see them.
I store all my bee keeping equipment in a 40′ high cube trucking container. Should I spray the entire container with B402 Certan, or just the frames? Also, do I reapply while the frames are in storage as a preventative, or is a one time application sufficient? Thanks for your time and efforts.
For myself, a one time application has worked for years. You only need to spray the beeswax comb.
Hi Charlotte . I just love reading our news. That BT article is a saver! Modern beekeeping with logical thoughts is so much better to understand our little ladies than forty years ago and what was taught in courses by Dr.Ambrose and the older beebooks.
Thank you so much for sharing your experience which will apply in most cases
Ursula
ps I sent you once a picture of a harlequin bee among honeybees on one of my native garden origin Rudbeckia laciniata. It never arrived as far as I can tell. If interested I can find it again and resend. Take care and keep up the good work.
Thank you. I don’t think I got a pic but I always love seeing pics of bees.
Charlotte – your statement about the coverage for the B402 says “The manufacturer (Vita-Health) maintains that a 5 oz bottle of B402 Certan will treat approximately frames of comb” — However there is no “Number’ between approximately and frames. Just an editing error I am sure but would be nice to know what that number is.
Thank you – that was a typo on my part.
What are some of the ways to store frames one intends to use in the next season?
Evah – here are some ideas https://carolinahoneybees.com/storing-honey-supers/