Best Varroa Mite Treatments (2025)

Why You Must Treat for Varroa

Varroa destructor isn't just annoying—it's an existential threat to your colony. These mites reproduce inside capped brood cells, feeding on developing pupae and transmitting deadly viruses including Deformed Wing Virus (DWV) and Acute Bee Paralysis Virus.

Mite populations double every 3-4 weeks during brood season. A colony that starts spring with 50 mites can have over 3,000 by August. At that point, the viruses they've vectored have already compromised the "winter bees"—the physiologically distinct bees that need to survive until spring.

The math is brutal: An untreated colony in most of North America has a near-100% chance of dying within 18 months of infestation. Treatment-free beekeeping exists, but it requires years of genetic selection and typically still results in 50%+ annual losses while you're developing survivor stock.

For beginners: treat. You can explore treatment-free approaches once you have the skills to manage the inevitable losses.

How to Monitor: The Alcohol Wash

You can't manage what you don't measure. The alcohol wash is the gold standard for accuracy:

Sugar roll alternative: Non-lethal but less accurate. Sugar rolls typically underestimate mite loads by 30-50%, especially in humid conditions. If you use sugar rolls, treat at lower thresholds to compensate.

How often to monitor: Monthly during brood season (April-September in most areas). More frequently if counts are rising.

Treatment Thresholds

Why lower thresholds in spring? Mite populations will explode during the summer buildup. A 1% count in April can become 10%+ by August if untreated. Early intervention prevents the exponential growth.

Why August matters most: This is when colonies raise "winter bees"—long-lived bees with enhanced fat bodies that must survive until spring. If mites infest these bees, they'll be virus-compromised and die mid-winter, even if your mite counts drop afterward.

Treatment Comparison Chart

Oxalic Acid — Our Top Pick for Winter

Oxalic acid is a naturally occurring compound (found in spinach, rhubarb) that's devastatingly effective against Varroa. It works by contact—mites absorb the acid through their feet and die within 24-48 hours.

The catch: Oxalic acid does NOT penetrate wax cappings. It only kills "phoretic" mites—those riding on adult bees. During brood season, 70-80% of mites are hiding in capped cells, so efficacy drops dramatically.

Application methods:

• Vaporization: Most effective. Uses a heated wand to vaporize oxalic acid crystals inside the hive. Requires a respirator and full protection—oxalic acid vapor is a lung irritant.
• Dribble: Oxalic acid dissolved in sugar syrup, dribbled between frames. Easier but less effective and can stress bees if overused.

Best timing:

• Late fall/early winter when the colony is naturally broodless (December-January in northern climates)
• During a summer brood break (after requeening or induced break)
• On new packages before they start laying

What we recommend: The Varrox Vaporizer or similar electric wands. Budget option: the Oxalic Acid Vaporizer from Brushy Mountain. Always use API-BIOXAL or pharmaceutical-grade oxalic acid.

Formic Pro — Best for Summer Treatment

Formic acid is the only registered treatment that penetrates wax cappings to kill mites reproducing inside brood cells. This makes it uniquely effective during brood season when other treatments only reach a fraction of the mite population.

Critical temperature constraint: Do NOT use if daily highs will exceed 85°F (29°C). Formic acid releases faster in heat, and elevated concentrations can kill queens. Check your 10-day forecast before applying.

Application: Formic Pro comes as pre-measured strips. Two strips placed on top bars, left for 14 days (or 20 days for extended-release). No feeding during treatment.

Side effects:

• Queen mortality risk of 2-4% (higher in hot weather)
• Temporary brood break is common
• Strong odor that can trigger robbing if entrance isn't reduced
• Worker bees may beard outside the hive during treatment

Pro tip: Ensure good ventilation and reduce the entrance during treatment. Some beekeepers prop up the outer cover slightly to increase airflow.

Apivar (Amitraz) — Synthetic but Effective

Apivar strips release amitraz slowly over 6-8 weeks, providing extended mite control without temperature restrictions. It's been a workhorse treatment for years.

The growing problem: Amitraz resistance is now documented in multiple US states. Before relying on Apivar, check with your local bee club or extension office about resistance in your area. Some regions report efficacy dropping below 50%.

Application: Two strips hung between brood frames, left for 42-56 days. Must be removed before honey supers are added—amitraz cannot contaminate honey for human consumption.

Best practice: Don't use Apivar more than once per year, and rotate with other treatment types to slow resistance development. If you used Apivar last fall, use formic or oxalic this year.

Apiguard (Thymol) — Organic Alternative

Apiguard is a thymol-based gel (derived from thyme) that bees remove and distribute throughout the hive. It's organic and doesn't leave residues, but efficacy is more variable than other treatments.

Temperature requirements: Best between 60-77°F (15-25°C). Below 60°F, bees won't remove the gel effectively. Above 77°F, evaporation is too rapid.

Side effects:

• Queen often stops laying temporarily during treatment
• Bees may abscond if colony is weak
• Can affect honey taste if used near harvest

Application: Two 50g applications, 2 weeks apart. Place gel tray on top bars in the brood area. Remove honey supers during treatment.

HopGuard 3 — Best for Packages and Nucs

HopGuard uses beta acids from hops (yes, the beer ingredient) to kill mites on contact. It's the only treatment besides oxalic acid that can be used during honey production, making it useful for packages installed during the flow.

The reality: HopGuard is messy—the strips feel like damp cardboard and leave residue. Efficacy is moderate (50-70%), so it's best used as a supplement rather than primary treatment.

Best use case: Treating packages or nucs when you can't use formic (too cold) or don't want to wait for a broodless period for oxalic.

Annual Treatment Rotation (Recommended)