Summer Management

Summer management means giving space, controlling swarming, providing water and shade and harvesting honey while the colony is at its most populous, then starting winter preparations with varroa control in late summer. Early summer decides the harvest, and late summer decides the following year: decisions made around August largely determine whether the colony will survive the winter.

What happens in a bee colony in summer?

In early summer the colony approaches its peak population; a strong hive contains tens of thousands of worker bees. With the main nectar flow, foragers work all day and the supers fill up. During this period a summer bee lives only a few weeks because of the heavy foraging work; the colony is constantly renewing itself.

After the main flow ends, many regions go through a nectar dearth. Laying slows down, drones start to be driven out of the hive and, towards late summer, the long-lived winter bees that will carry the colony through the winter begin to be reared.

Early summer: what to do during the main flow

• Super on time: A super (upper box) is given when the bees have spread out to the last frames of the existing box and fresh nectar is starting to come in. A super given late both limits storage and triggers swarming.
• Using a queen excluder: A queen excluder placed between the brood box and the super stops the queen from going up and laying in the super; it makes harvesting and extraction easier.
• Keep up swarm control: Until the swarming season is over, hives are checked about every 7 days and queen cells are looked for.
• Add a new super above or below the filling one: When a super is 70–80% full, a second super is added; waiting leads the bees to fill the brood box with honey (leaving the queen no room to lay).

Why are water and shade essential in summer?

The brood nest must be kept at a constant temperature of about 34–35 °C. On hot days bees fan their wings at the entrance to ventilate, and cool the hive by evaporating the water they bring in. As a result, water consumption rises sharply in summer.

• Clean, constant water: Set up a water source near the apiary with floating material (sticks, stones, straw) in it so bees do not drown. It is important that it does not dry out; once bees learn a water source, they stick to it.
• Shade: In very hot regions, sites that get afternoon shade or a shade cover over the hive help. A light-coloured roof absorbs less heat.
• Ventilation: In very hot spells the entrance is opened fully. Bees clustering on the front of the hive like a "beard" have usually come out because of the heat; on its own this is not a sign of swarming, but it should be assessed together with lack of space.

When and how do you harvest honey?

The harvest takes place when the honey is ripe and the bees have capped the cells with wax. Unripe honey contains too much water and can ferment in storage.

1. Check ripeness: Most of the frame (usually three quarters) should be capped. For partly capped frames, moisture is measured with a refractometer; the usual target is around 18% or below, and for most honeys the legal upper limit is 20%.
2. Clear the bees from the super: A clearer board, a brush or gentle shaking can be used. If the clearer board is put on the day before, the harvest goes much more calmly.
3. Little smoke: Too much smoke can taint the honey's aroma; use only as much as needed.
4. Work quickly and keep things covered: Harvesting during a dearth starts robbing; carry supers covered and never leave honey exposed.
5. Leave stores for the colony: Honey in the brood box is not taken. If there is a dearth after the harvest, the colony may go hungry.
6. Extract separately by source: Keeping honeys from different flowering periods separate makes it possible to obtain monofloral honey and to maintain quality.

The midsummer nectar dearth: robbing and pests

After the main flow, hive weights begin to fall. The main risks in this period are:

• Robbing: Strong colonies rob weak ones. The signs are bees fighting at the entrance, crumbs of torn comb in front of the hive and bees zigzagging as they probe the entrance. Reduce the entrance of weak colonies, keep inspections short and never leave syrup or honey outside.
• Running out of stores: Monitor hive weight; if the dearth drags on and stores run low, feeding may be needed (give syrup in the evening and inside the hive).
• Wasps and hornets: Pressure from hornets and wasps (yellowjackets) increases towards late summer. In the hot regions of Türkiye, the Oriental hornet (Vespa orientalis) in particular can bring down weak colonies by hunting in front of the entrance. Reducing entrances and using traps around the apiary lessen the pressure.

Why is late summer the turning point of the beekeeping year?

Late summer is the most often underestimated but most decisive period. The winter bees reared in these weeks have to live for months. A winter bee with a well-developed fat body makes it to spring; a bee born weak under a varroa load dies within a few weeks, and the colony dwindles away in midwinter.

When brood rearing starts to decline, Varroa destructor mites concentrate on the remaining brood and the adult bees; the mite load rises rapidly during this period. Therefore:

1. Measure the mite level: Alcohol wash, icing sugar or sticky board methods are used. In late summer, more than 2–3 mites per 100 bees is considered the treatment threshold in many guides.
2. Treat immediately after the last harvest: The mite load must be brought down before winter bees start to be reared. Although it varies by region, this is usually around August; treatment carried out after the winter bees have been reared is often too late.
3. Authorised products only: Authorised products based on organic acids, thymol or synthetic active substances are applied according to the label instructions and after the supers have been removed. Repeating the same active substance year after year leads to the development of resistance.
4. Measure the result again: Only a repeat count shows whether the treatment worked.

Late summer checklist

Common summer mistakes

• Supering late: Lack of space leads to both swarming and a lost harvest.
• Extracting unripe honey: Uncapped honey can ferment.
• Taking the honey in the brood box as well: This leaves the colony hungry during a dearth.
• Keeping the hive open for a long time during a dearth: This starts robbing, and once robbing has started it is hard to stop.
• Leaving varroa until September–October: By then the winter bees have already been damaged.