Bees make honey from nectar. During the spring and summer the colony sends out thousands of foraging bees who collect the vast amounts of sugary water produced by flowering plants as a bi-product of photosynthesis. A single cherry tree can produce 2kg of nectar per day and honeybees have evolved a long straw-like tongue for collecting it.
The best nectar collectors
Honeybees are simply the best collectors of nectar around, they are so good that they have very little competition from other insects. But because there are not enough bees to collect it all, thousands of tonnes of nectar goes to waste every year.
The amount of nectar that the bees can collect is influenced greatly by the weather. In very wet summers the nectar produced by plants and trees is much diluted and therefore of poor quality. In very hot weather the plants stop producing nectar entirely.
The amount of water in the nectar is a measure of its quality and your bees will actively source the flowers producing nectar with the lowest percentage of water and the highest percentage of sugar. In a good season the bees will actually become quite discerning about this and foraging bees who return with watery nectar will have their load rejected by the hive bees and sent out into the field to do better.
The foraging bees transfer the nectar at the entrance of the hive to other bees who have the job of packing it into the storage cells. Firstly, they will make sure there is enough instant access honey around the brood but when a surplus occurs they will need extra storage space.