Varroa Management in Washington State

Washington State is two different beekeeping worlds separated by the Cascades. West of the mountains, the Puget Sound lowlands have a maritime climate with mild winters, wet springs, and relatively cool summers. East of the mountains, the Columbia Basin and Yakima Valley have an arid continental climate with hot, dry summers and cold winters. Both sides of the Cascades have excellent beekeeping, but varroa management timing differs meaningfully between them.

West of the Cascades: Maritime Climate

Western Washington, including the Puget Sound area, Willamette Valley spillover, and the Olympic Peninsula lowlands, has a mild maritime climate. Winters are wet and cool rather than bitterly cold. Temperatures rarely drop below the mid-20s Fahrenheit even at low elevations. Brood rearing may continue at a reduced level through December and January rather than stopping completely.

The broodless period in western Washington is shorter and less reliable than in eastern Washington. Some colonies remain with brood year-round during mild winters. This limits the effectiveness of OAV treatment during natural broodlessness and means some beekeepers on the west side must use OAV under brood-on conditions or create artificial brood breaks.

West side management calendar:

• August: Apivar after the summer main flow. Blackberry and fireweed are primary summer sources.
• October: Strips out, post-treatment count.
• December to January: Monitor for broodlessness. Apply OAV if broodless, or apply three OAV treatments five days apart if brood is present.
• March to April: Pre-spring mite count. Treat if needed before supers go on for the maple and fruit tree flow.

East of the Cascades: Continental Climate

Eastern Washington, including the Yakima Valley, Columbia Basin, and Wenatchee area, has a very different beekeeping profile. Cold winters with reliable broodlessness, hot and dry summers, and the massive tree fruit and hop growing industries create a beekeeping landscape dominated by pollination services.

Broodlessness in eastern Washington typically occurs from late November through February, providing an excellent OAV treatment window. Temperatures regularly drop below freezing for extended periods, ensuring a complete cessation of brood rearing.

East side management calendar:

• August: Apivar after the main summer flow ends. Mint, clover, and wildflowers support summer production.
• October: Strips out, post-treatment count.
• December to January: OAV during confirmed broodlessness. In years with extreme cold, verify the cluster is accessible before treating.
• March: Pre-pollination placement mite count for beekeepers supplying fruit tree bloom.
• April to May: Apple, cherry, and pear pollination season. MAQS can be used with supers on if needed and temperatures are within range.

Pollination Services and Varroa

Washington State's tree fruit industry, including apple, cherry, pear, and blueberry, is one of the largest in the nation. Many Washington beekeepers provide pollination services as a significant revenue stream. Varroa management interacts with pollination contracts in several ways.

Pre-placement colony assessments should include mite counts. Delivering high-mite colonies to a grower risks hive health during the contract period and damages your professional reputation. Aim to have post-treatment mite counts below 1% before pollination placement.

During pollination contracts, MAQS is the primary treatment option with supers on. Temperature conditions in April in eastern Washington can be cold, so confirm temperatures are within the MAQS effective range before applying. Cool nights can drop below the effective threshold even when days are warm.

Post-pollination treatment is important. Colonies returning from orchard placements often have elevated mite counts due to hive stress and exposure to other colonies. Count mites within a week of return.

Documenting Washington State Operations

Washington's diversity in operation type (from small hobby apiaries in the San Juan Islands to large pollination operations in the Yakima Valley) means the record-keeping needs vary widely. VarroaVault's flexible structure supports both small hobby operations with a handful of hives and commercial operations with hundreds of hives across multiple east-side and west-side yards.

The multi-apiary management tools are particularly useful for Washington beekeepers running yards on both sides of the Cascades with different management schedules. Yards on the west side with brood-on OAV timing and yards on the east side with natural broodless period timing can be managed on independent schedules within the same account.