If there's one thing that separates beekeepers whose colonies survive from those whose don't, it's this: managing varroa mites. These tiny parasites are the number-one killer of honeybee colonies, and ignoring them is the most common beginner mistake. The good news — it's very manageable once you know the rhythm. Here's the simple version.
Varroa mites are a parasite that weakens bees and spreads disease. Monitor your mite levels regularly (an alcohol wash or sugar roll), and treat when they cross the threshold — especially in late summer, before winter bees are raised. Treating on time is the single biggest thing you can do to keep your colony alive.
Why varroa matters so much
Varroa mites feed on bees and their developing brood, and they spread viruses that cripple a colony. Left unchecked, mite levels explode by late summer and the colony collapses over winter — often the real reason behind a "mysterious" dead-out. Nearly every colony has some mites; the job isn't to eliminate them, it's to keep them low.
Step 1: Monitor (don't guess)
You can't manage what you don't measure. The two common beginner methods:
- Sugar roll — coat a sample of bees in powdered sugar, shake out the mites, count them. Non-lethal to the bees.
- Alcohol wash — more accurate; a sample of bees is washed to dislodge mites. Kills the sample but gives the truest count.
Check every few weeks in the active season. If your count crosses the recognised threshold (commonly around 3 mites per 100 bees), it's time to treat.
Step 2: Treat on time
There are several approved treatments — your climate and the season decide which. Common options beginners use:
- Oxalic acid — very effective when there's little or no capped brood (e.g. mid-winter). Cheap and widely used.
- Formic acid — can penetrate capped brood and works across warmer temperatures.
- Thymol-based treatments — a gentler, essential-oil approach.
Always follow the product label and your local guidance exactly — temperature and timing matter. The most important window is late summer / early autumn, before the colony raises the long-lived "winter bees" that must be healthy to survive.
Frequently asked questions
How often should I check for varroa?
Every few weeks through spring, summer and early autumn, and always before and after treating so you know it worked.
Can I keep bees without treating for varroa?
Some experienced keepers pursue treatment-free approaches with mite-resistant stock, but for beginners it's a common route to a dead colony. Learn to monitor and treat first.
When is the most important time to treat?
Late summer to early autumn, before winter bees are raised. Get this window right and your colony's odds of surviving winter jump dramatically.
Informational only — always follow the treatment product label and your local regulations, and lean on a local club or mentor. Contains affiliate links; we may earn a small commission at no extra cost to you.