Author: Tony Wilsmore

Issue: April 2026

Subject: Practical Guidance on Autumn hive pack down, climate control, nutrition and varroa management to help colonies survive winter now that Varroa is established in Victoria. 

Autumn is one of the most important times of the beekeeping year. Decisions made in late summer and autumn determine whether colonies simply survive winter or emerge strong and productive in spring.

Good pack down practice ensures bees can maintain a stable nest environment, access adequate food stores, and avoid unnecessary stress from pests and pathogens. This has always been important, but it is especially critical now that Varroa is present in Australia. High mite levels weaken winter bees and increase colony susceptibility to disease and pests, putting hives at risk during the colder months.

Preparing colonies properly for winter can be considered under three main areas: climate control, nutrition, and pathogen and pest management.

Climate Control: A Dry, Warm Nest

Healthy bees need a dry, draft-free nest that can be maintained with minimal energy expenditure. During winter, the colony clusters to generate heat. If the hive has excessive ventilation or too much empty space, bees must work harder to maintain cluster temperature, consuming more stores and weakening the colony.

Several simple actions can help maintain a stable hive environment.

• Review ventilation. While airflow is beneficial in summer, excessive ventilation during winter can create cold drafts and condensation. Closing off ventilated bottom boards or roof vents can help the colony maintain warmth. 
• Reduce the volume of the hive. Surplus honey boxes should be removed before pack down so that the colony occupies a space it can effectively manage. A smaller hive volume helps bees retain heat and defend the colony against pests.
• Consider insulation. Insulating the hive roof can reduce heat loss and condensation during cold weather. 
• Reduce the entrance size. Smaller entrances help bees conserve warmth and improve their ability to defend the hive against robbing and pests. 

Nutrition: Feeding the Winter Bees

Autumn is often a period of declining forage. Nectar flows slow, and colonies may become defensive as food becomes scarce. At the same time, the colony begins raising winter bees, which are physiologically different from summer bees and must live for several months. For this reason, nutrition in autumn is critical.

Winter bees must develop with adequate nutrition to ensure strong colonies in spring. Colonies also need sufficient food reserves located close to the brood nest so that the cluster can access stores during cold weather when movement within the hive is limited.

Beekeepers should assess colonies carefully and identify weak hives early. Weak colonies may need strengthening, protection, or combining with stronger colonies before winter. Feeding may also be necessary if honey reserves are insufficient. Moving honey frames closer to the brood nest can help ensure bees have access to food during winter clustering.

For a single brood box setup in Melbourne, a useful rule of thumb is to aim for at least four full frames of honey in the brood box by late April. Conditions vary across regions, but ensuring adequate stores is essential for winter survival. Reducing the entrance size can also help protect colonies during this period when robbing pressure may increase.

Pathogens and Pests: Clean Hives and Low Varroa Levels

Strong colonies heading into winter require both a clean environment and low pest pressure. Hygiene plays an important role in reducing pathogen load. Old wax, propolis buildup, and contaminated comb can harbour disease organisms and pests. Cleaning hive components before winter is therefore good practice.

Frame bars and hive boxes should be scraped clean of wax and propolis. Wooden hive boxes can be flame sterilised using a blowtorch or heat gun to destroy pathogens on the surface. Old frames that have been cleaned can be disinfected before reuse. Rotating out older brood frames is also recommended, as old comb can accumulate residues and disease spores over time.

Polystyrene hive components require a different approach. These can be cleaned using washing soda to remove wax and propolis and then disinfected using bleach or an appropriate disinfectant such as Virkon S.

Pest management is equally important. Empty comb and unused boxes should be removed to reduce the risk of wax moth and small hive beetle infestations. Most importantly, colonies should be tested and treated for varroa before winter bees are raised. Maintaining low mite numbers going into winter is critical for colony survival. Colonies entering winter with high mite loads often produce weakened winter bees and may collapse before spring. As with other pack down measures, reducing the entrance size can also assist the colony in defending itself against pests.

The Key to Strong Spring Colonies

Preparing colonies for winter is not a single action but a combination of management decisions made throughout autumn.

By focusing on climate control, nutrition, and pest management, beekeepers can greatly improve the chances that their colonies will emerge from winter healthy and productive.

Good pack down practices help ensure that when spring arrives, colonies are ready to build rapidly, take advantage of early nectar flows, and continue the cycle of strong beekeeping seasons.