Karl Colyer

September is a month of consolidation as the bees start to make their preparations and changes for winter.  Bee numbers continue to reduce.  Drones may no longer be present in many hives.

For most beekeepers in the UK, September marks the transition from summer towards winter. The bees are fully aware of the shortening days and cooler nights and several important activities are taking place within each hive.

A time for observation
The amount of brood will be reducing in line with the queen’s reduced rate of egg-laying. The general shift now is from raising new bees for foraging to the preparation of winter bees. These bees will live longer than any of the summer bees, often for up to six months as compared to the more usual six weeks for a summer worker bee. The emphasis here is to maintain the existing population for winter.

Ripening of nectar into honey will continue until all cells are capped. It will take longer to reduce the moisture content of nectar as the nights grow cooler and longer. You may notice your bees becoming more defensive in nature. This can partly be due to less nectar and pollen being available so more foraging bees are in the hive protecting their valuable winter stores from robbing. Weak colonies are typically more susceptible to robbing, particularly if the entrance is too large to be defensible. You may see that bees are storing more pollen than usual. This will be done in anticipation of having to feed the small number of brood raised over winter as well as for general colony nutrition.

Grass in the entrance to reduce robbing

One thing you may also notice is that the bees will still be collecting propolis to fill any small gaps, cracks or crevices within the hive. Plugging the draughts and gaps will improve insulation and protect the hive from potential overwintering intruders. If your bees are using propolis to reduce the entrance size, make a note of this and learn their preference for their overwintering entrance size and shape.

In terms of Varroa management, this time of year tends to be pivotal for the bees. Mite levels are likely to be at their highest for the season and your bees should, hopefully, be grooming themselves and other bees to manage the mite population. If you have to apply a chemical intervention to support your bees, make a note of the treatment type, date, quantity and duration. You will need to keep these records and they are useful for understanding which of your colonies are best dealing with mites in your apiary.

Overall, the colony population is now consolidating towards its winter configuration. Older foraging workers will be dying out, drones will soon be ejected from the hive and a more compact population will develop and maintain itself for the arduous task of keeping warm, protecting the queen and winter survival. The cooler the nights, the tighter the cluster and the longer it will take for the bees to start flying the next day. As well as foraging flights when weather permits and forage is available, the recently emerged bees will perform their orientation flights to familiarise themselves with their hive’s location and build up their muscles. Other than this, the hive entrance will be steadily quietening down at this time of year.

Some nucs in September

All the above activities will vary depending upon your latitude, altitude and the direction that your apiary is facing relative to the sun and weather. The condition of the colony also influences its ability to properly prepare for winter. If you have several colonies, observe which ones are struggling to keep up with the apiary average. You may have to make a tough decision. You can either prop up the colony with feed (a short-term but not sustainable approach), unite it will another colony (a consolidation approach) or leave the weak colony to its own devices. If necessary, move some of the winter stores in the hive to bring it around and above the cluster. Only move stores between hives if you are proactively monitoring for diseases and pests. Winter can be tough on bees but it is one of the best selection tools to ensure that only locally adapted bees naturally remain in an area.


Get to know your bees

If you are taking honey off in September, be very prudent, not greedy. The bees cannot recover quickly or easily from the loss of their resources as forage is scarce and the weather is both darker and cooler for longer periods. Even sugar syrup is more time-consuming and energy-consuming to convert to honey at this time of year and it is a lower quality sustenance for the overwintering bees, compared to honey.

Many bee colonies can successfully overwinter their cluster and all their food requirements within a single brood box. Reducing the size of overwintering hives to give the bees just enough space and no excess will make it easier for them to maintain their warmth over the winter. A smaller hive space will require less energy to heat and will bring all the resources together, helping the bees to more effectively survive the winter.

Photos:  Karl Colyer