Pick a treatment, enter your expected daytime high, whether the honey supers are on, and your brood state — the checker reads the same label-aligned constraint rows the MiteWindow iPhone app ships (temperature band · supers legality · brood requirement · 12-month class rotation) and tells you yes or no, with the reason, plus what a better window looks like. Below it: the seasonal mite wash threshold quick-check. Free, no sign-up, no tracking.
Constraint rows are ported from the MiteWindow app's label-aligned product dataset; the region sets mirror what the app offers per region, not a per-country approval database. Always follow your product's label — the label is the law. The 12-month class rotation is the app's own planning model, not label text.
The app's default thresholds: 6 / 300 (2%) March–June · 9 / 300 (3%) July onward — Honey Bee Health Coalition / university-extension guidance, user-adjustable per apiary in the app.
MiteWindow — Varroa Planner for iPhone runs the same constraint engine this page does — free here for a single read — on a live per-hive season timeline:
It's mid-July: the late-summer treatment window (August–September) — the main knockdown after the harvest, before winter bees are raised — is exactly what the season track is for. Plan it against your flow and your forecast now.
Get the season planner on theFree for up to two hives — the complete instrument, not a teaser. One-time $12.99 unlock for unlimited hives & firing re-check notifications. No subscription, no ads, no account.
rotation > supers > brood > temperature — if two constraints block a product, you're shown the one the app surfaces first (a repeated class shows ROTATE even when the supers also refuse it).The constraint rows (temperature band, supers legality, brood requirement, application length, repeats and re-check offset per product) are ported verbatim from the app's product dataset — label-aligned data rows, the same numbers the iPhone app projects a season from.
When a mite wash crosses the seasonal threshold — not by the calendar. The app's shipped defaults (HBHC / university-extension guidance): 6 mites per 300 bees (2%) in March–June, 9 per 300 (3%) from July onward. Wash ~300 bees in alcohol, count, and read the number above. Whether today is the day is the second half — temperature, honey flow and brood state gate the actual window, which is what the top checker reads.
In the app's default rule set: 6/300 spring · 9/300 summer–fall. At or over → open a treatment window. Under → keep monitoring and re-check. Both numbers are user-adjustable per apiary in the app, with the source for each default shown next to it.
10–29.5 °C (50–85 °F) daytime highs, per the label-aligned row for Formic Pro and MAQS. The band is enforced strictly on both sides — too hot and the release is too aggressive, too cold and it's too weak to work. In a heat wave the honest answer is wait for the first cool week, and that is exactly what the checker will tell you.
Formic acid (Formic Pro, MAQS) is the only class marked supers-legal in the app's dataset. Apivar (amitraz), Apiguard (thymol), oxalic acid and Bayvarol are refused during the honey flow — their window opens after the supers come off, which is why the main knockdown is a late-summer job planned around the harvest.
Not in the app's product rows — oxalic's binding constraint is brood. The dribble requires a broodless colony; vapor prefers one and schedules 3 passes, 5 days apart when brood is present. Mites riding inside capped cells are sheltered from oxalic, so the right window is a brood break (~21 broodless days in the app's model) or the late-autumn broodless period.
Repeating one active ingredient selects for resistant mites. The app reads your hive's own track for classes used in the past 12 months and refuses a repeat into the next slot, surfacing the legal alternatives instead. Tell the checker what you last used and it applies the same read.