Propolis: What is it? Why do honeybees need it?

Propolis is a substance that honeybees create by mixing enzymes in their saliva with beeswax and resins collected from the buds and bark of trees. Trees secrete these sticky resins from their growing buds to protect them against water loss, high & low temperatures, microbes & insects.

Honeybees will always discard broken pieces of beeswax from their hive instead choosing to create fresh new wax from special glands on their abdomen, however they will always collect and recycle old propolis when given the opportunity.

The photo above shows some of our honeybees collecting old propolis from the side of a frame of old brood comb which I was just about to melt down in my wax melter in order to make some beeswax candles. These honeybees are using their tongues and jaws to break off pieces of propolis which they then deposit in their pollen baskets on their hind legs. They will then return to their hive and deposit it where it's needed.

All honeybees create and use propolis although some subspecies create more and some less than others. Propolis plays a very important role in maintaining a healthy environment within the beehive by disinfecting and sterilising it. Propolis is most often brown in colour & extremely sticky with a very pleasant medicinal fragrance containing antimicrobial, antiviral, antiseptic, antiseptic & antifungal properties.

Honeybees coat the inner surface of their hive with propolis, filling cracks, rough surfaces and any gaps less than a quarter of an inch in size. Honeybees like to have darkness within their hive and they will use propolis to block up any gaps where light gets through and also to reduce the size of the entrance hole into their hive.

Worker bees also coat and polish the internal structure of brood comb cells with a thin layer of propolis. These are the cells where the queen lays eggs that grow and develop into the next generation of honeybee.

In 2021 a group of Italian researchers conducted experiments (cited below) into the benefits of this thin coating of propolis within brood cells and they came to the conclusion that it acted as an effective acaricide to kill mites. They discovered that Varroa mite levels were reduced by up to 20% as a direct result of propolis being present in brood comb.

Honeybees cluster in a ball around their queen to keep her warm during cold weather in winter and sometimes rodents can break their way into the hive lured by the smell of honey and the inactivity of the honeybees. However the honeybees can break cluster on occasion and attack the mouse/rat and sting it to death. The honeybees have developed a clever solution to dealing with this dead decomposing rodent body which is too heavy for them to remove from their hive whereby they coat the body of the rodent entirely in propolis essentially cocooning and hermetically sealing it so it won't effect the health of the hive.

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