Varroa Management Plan
A season-long varroa control schedule for production colonies (Wirtschaftsvölker) and nucleus colonies (Ableger), based on the proven concept by Dr. Pia Aumeier, Dr. Gerhard Liebig, and Dr. Otto Boecking. The key rule: never treat on a fixed schedule — measure the natural mite fall first and treat only when a threshold is exceeded.
Production colony
Cut drone brood
Biotechnical- At cherry blossom, expand every colony with a queen excluder and honey super, and hang an empty drone frame in the upper brood box between the outermost comb and drawn combs.
- Cut the frame out after 14 days at the earliest and 24 days at the latest — never let the drones emerge. Repeat as often as possible from April to July.
Nucleus colony
Spray with lactic acid
Lactic acid- In the broodless phase right after the nucleus is made up, spray the bees on every comb (both sides, about 3 bursts per side) with 15% lactic acid.
- With heavy varroa infestation, repeat the treatment after a few days.
Wear gloves, long clothing, and safety glasses. Sprayed colonies must not be used for honey production in the same year.
Production colony
After the last honey harvest: insert the sticky board for exactly 3 days and count the natural mite fall.
Natural mite fall above 10 varroa per day:
1× emergency treatmentFormic acid
Very rarely necessary. Below the threshold, do not treat — spare the brood and bees.
Nucleus colony
3-day mite-fall count.
Natural mite fall above 5 varroa per day:
1× emergency treatmentFormic acid
Very rarely necessary. Below the threshold, do not treat.
Production colony
Start late-summer care
Formic acid- Condense the colony by removing the lower brood box (comb hygiene).
- 1× treatment with formic acid.
- Then feed the winter stores in one large portion.
Alternative: make the colony broodless with “divide and treat” and use oxalic acid instead of formic acid — see the detailed guide below.
Nucleus colony
No treatment
- Simply keep feeding small portions and let the colony develop and draw out its combs.
Production colony
After feeding is finished: 3-day mite-fall count.
Natural mite fall above 5 varroa per day:
1× treatmentFormic acid
Below the threshold, no further treatment is needed.
Nucleus colony
3-day mite-fall count.
Natural mite fall above 1 varroa per day:
1× treatmentFormic acid
Winter feeding follows after the treatment.
Production colony
In the broodless winter period: 3-day mite-fall count.
Natural mite fall above 1 varroa per day:
1× residual de-mitingOxalic acid
Trickle 30–50 ml of 3.5% oxalic acid solution onto the bees in the occupied seams. Below the threshold, no treatment is needed.
Nucleus colony
In the broodless winter period: 3-day mite-fall count.
Natural mite fall above 1 varroa per day:
1× residual de-mitingOxalic acid
Trickle 30–50 ml of 3.5% oxalic acid solution. Below the threshold, no treatment is needed.
Natural mite fall per day, measured over exactly 3 days with a sticky board under a screened floor.
The recipe's success factor: record the natural mite fall with screened floors and sticky boards instead of treating on a fixed calendar. Every treatment is matched to the actual infestation and the colony's development. Used nationwide since 2008 in 140 hobby, professional, and institute apiaries, this approach kept colony losses at 7% or less — with no chemicals during the nectar flow and no residue-forming or resistance-building varroacides.
Concept by Dr. Pia Aumeier, developed with Dr. Gerhard Liebig and Dr. Otto Boecking at Ruhr-Universität Bochum in the “Imkerberatung NRW” project; divide-and-treat method as published in Deutsches Bienen-Journal (DNB 07/2017).