How to treat varroa between honey flows with Amiflex and Amiflex 2.0?

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By mid-season, Varroa pressure can climb fast. Brood is at its peak, mite reproduction accelerates with every brood cycle, and the gap between “manageable” and “out of control” can close in a matter of weeks.

But here’s the problem most beekeepers run into: by the time you spot the damage, it’s already too late. And waiting for the end-of-season treatment window means letting mites multiply unchecked through your most productive months.

This is exactly where a flash treatment between honey flows makes sense. In this guide, we’ll walk you through when, why, and how to use Amiflex (Canada) / Amiflex 2.0 (USA) to lower mite infestation during the season without disrupting your honey production.

Why mid-season varroa control matters?

Varroa populations don’t wait for your end-of-season treatment window. According to the Honey Bee Health Coalition (HBHC), in colonies with brood, uncontrolled mite populations can double monthly. That doubling is exactly what catches beekeepers off guard between June and August.

The HBHC recommends Varroa treatment thresholds based on the colony phase. During the Peak Population phase, which corresponds to mid-season in most North American operations, any colony with a Varroa mite level above 2% infestation (2 mites per 100 adult bees) should be treated promptly.

This is a problem if you still have a honey flow coming up. Most Varroa treatments either take weeks to act, require honey supers to be removed for an extended period, or come with temperature constraints in use that don’t match summer conditions. The result: many beekeepers postpone treatment, hoping the bees will “hold on” until the end of the season and the reality is that they rarely do.1

This is where a flash treatment changes the game.

What's a flash treatment, and why use one between honey flows?

A flash treatment is a short application  that hits the mite population  fast, decreasing phoretic mite levels in a short period of time It is commonly used during the honey flow season.

Our Amiflex / Amiflex 2.0 is an amitraz-based gel flash treatment. It is a one 7-day treatment application of two doses of 3 mL per brood box  on the brood frames applied with a pre-loaded dosing gun on flat wooden sticks. After 7 days, you remove the wooden sticks along with any remaining gel, and you’re done! You can put your honey supers back on the same day.

Amiflex flash treatment packaging for Varroa mite control in honey bees

This flash treatment is the right tool for a specific job: reducing mite infestation during the season, between two honey flows, or right before your end-of-season treatment. Note that this I not  a replacement for your main treatment, it is an additional tool in your integrated varroa mite management strategy.

When to apply Amiflex / Amiflex 2.0 between honey flows?

The good news: timing is flexible. You can apply Amiflex / Amiflex 2.0 immediately after removing your honey supers2. No need to wait. And once the 7-day treatment is over, you can put the supers back on right away. There’s no withdrawal period.

That means that a complete treatment cycle takes exactly 7 days from supers off to supers back on.

A few real-world examples:

  • USA, Northeast: between the spring tree flow (locust, basswood) and the summer wildflower flow, you typically have a window of 2-3 weeks. A 7-day Amiflex 2.0 application fit comfortably in that gap.
  • Canada, Prairies: between the canola  and the clover/alfalfa flow, beekeepers often face a brief window where mite pressure surges. Amiflex is well-suited for that window.

The point isn’t the specific flow. The point is: if you have at least 7 days without honey supers, you have time for Amiflex / Amiflex 2.0.

Beekeeper applying Amiflex gel with dosing gun on brood frame for Varroa treatment
© Thierry Vincent

How many applications do you need?

This is where assessing your situation matters.

One application is the standard case. If your mite count is at or near the HBHC treatment threshold, a one 7-day application is enough to bring your colonies back under control before the next flow.

Two applications are recommended when infestation is high. If you observe an unusually mid-season high mite count  closer to what you’d normally see at end-of-season, you’ll want a second application. Here’s the protocol:

  • First application: 7 days
  • Break: 7 days (no treatment)
  • Second application: 7 days

This 21-day cycle covers a full Varroa reproductive cycle inside capped brood, giving you a more complete knock-down. Note: this counts as two of the maximum applications allowed per year.

What efficacy can you expect?

It depends on whether brood is present or not.

When brood is present (which is the case in mid-season):

  • One application: 56% efficacy on average in double brood chamber Langstroth hives, 69% efficacy in Dadant hives.3,4
  • Two applications: 81 to 83% efficacy on average (tested on both Dadant and Langstroth hives)3,4

When brood is absent (typically late season or after a brood break):

  • One application: 99 to 100% efficacy, with 93 to 94% achieved in the first 24 hours after application.5

This is why Amiflex / Amiflex 2.0 isn’t designed to replace your main end-of-season treatment. It’s the tool that effectively reduces the mite infestation pressure during the season so Amiflex / Amiflex 2.0 helps to prepare honey bee colonies for a successful overwintering.

 

Close-up of Amiflex applicator depositing gel on wooden sticks in a beehive
© Thierry Vincent

Step-by-step application

Read entire label, use strictly in accordance with precautionary statements and directions, and with applicable provincial or territorial and federal regulations.

The application takes just a few minutes per hive. Here’s the process:

  1. Confirm no honey supers are on. Treatment must always be carried out without honey supers.
  2. Load a cartridge into the dosing gun.
  3. Place two wooden sticks (called “wooden supports” in the instructions) on the top bars of each brood box.
  4. After priming the tool, apply 2 doses (2x3mL = 6mL) per single-body hive, or 4 doses (4x3mL = 12 mL) per double-body hive. That’s a one line of gel on each of the two wooden sticks  per brood box. Place the lines of gel in the center of the brood area or in the center of the bee cluster. Avoid end frames for application.
  5. Leave for 7 days.
  6. On day 7, remove the wooden sticks and any leftover gel from the top bars.
  7. Put your honey supers back on, immediately if you want.

No temperature constraints during application. You can apply Amiflex / Amiflex 2.0 -under any weather conditions, as long as bees are active in the hive.

One note on storage: while there’s no temperature restriction during use, storage temperature does matter. Please read the label before storing your product.

For a complete step-by-step illustrated guide, download the Amiflex / Amiflex 2.0 practical sheet [USA version] [Canada version] or the corresponding fact sheet for Canada from your distributor.

Don't skip the post-treatment check

Treating without checking the result is treating blindly. We recommend a post-treatment sampling to confirm that mite levels have dropped below threshold.

Use the Varroa EasyCheck tool with the alcohol wash method on a 300-bee sample. If your post-treatment count is still above threshold, you may need a second application or a complementary intervention.

Sampling before AND after every treatment is the foundation of any serious varroa management program.

Where Amiflex / Amiflex 2.0 fits in your overall strategy?

A flash treatment isn’t a silver bullet. It’s one tool in your integrated varroa mite management toolbox, alongside:

  • Monitoring (sugar shake or alcohol wash, with Varroa EasyCheck for example)
  • Long-acting treatments like Apivar 2.0, for end-of-season control
  • Management practices (brood interruption, drone brood removal, requeening)
  • Other authorized chemical and organic treatments used in rotation

Rotating active ingredients is essential to slow the development of resistance. Amiflex / Amiflex 2.0 uses amitraz, the same active ingredient as Apivar and Apivar 2.0, so it’s important to plan your season to alternate active ingredients across the year rather than relying on amitraz alone.

Want to build a complete varroa management strategy for the season? Download our integrated varroa mite management guide for a structured approach.

Where to get Amiflex / Amiflex 2.0?

  • USA: Amiflex 2.0 is available through Mann Lake in all U.S. states [except California and Oregon – still pending approval]
  • Canada: Amiflex is available through

Got questions? Visit our FAQ page or contact our team.

Strong colonies start with smart varroa control. We’re here to help you get there.

  1. Winter losses according to the date of medication administration (all treatments combined – France, Eastern Region – Data from 2010 to 2020) : Page 4 of the following report: https://www.ada-grand-est.org/wp-content/uploads/2024/07/enquetes_pertes_hivernales_grand_est-Bilan-10-ans.pdf

2. As long as the bees are active, which is necessarily the case at this time of year.

3. Testapi. (2021). Assessment of effects of one or two applications of “FLASH” formulation on honeybee colonies in Dadant shaped hives and associated efficacy against Varroa destructor. GLP Study No. 514-2021.

4. Testapi. (2021). Assessment of effects of one or two applications of “FLASH” formulation on honeybee colonies in double Langstroth shaped hives and associated efficacy against Varroa destructor. GLP Study No. 552-2021.

5. Testapi. (2021). Assessment of effects of a single application of multiple doses of “FLASH” formulation on broodless honeybee colonies in Dadant and double Langstroth shaped hives and associated efficacy against Varroa destructor. GLP Study No. 507-2021.

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