Sugar Syrup for Bees: Ratios, Recipes and Sugar Types

Syrup concentration is chosen to match purpose rather than being fixed year-round. A lighter syrup, roughly equal parts sugar and water by weight, is thinner and easier for bees to process quickly, making it suited to spring stimulation, routine maintenance feeding and emergency response in mild weather. A heavier syrup, around 2 parts sugar to 1 part water by weight, is thicker and closer to the concentration of ripe honey, making it more efficient for building winter stores in autumn since it requires less evaporation effort from the colony before it can be capped.

Both syrups are made the same simple way: heat water, add white granulated sugar gradually while stirring until fully dissolved, then allow to cool before feeding. Sugar should never be boiled for an extended period or heated much above the point of dissolving, since prolonged high heat can produce hydroxymethylfurfural (HMF), a compound that is toxic to bees in quantity; gentle warming to dissolve the sugar is all that's needed.

White granulated cane or beet sugar is the standard choice: it's a near-pure sucrose source, cheap, and well tolerated by bees. Brown or unrefined sugars, and any sugar containing molasses, should be avoided, since the additional compounds they contain can cause digestive upset, particularly in bees confined over winter.

Invert sugar is sucrose that has been chemically split into its component fructose and glucose, either commercially or through controlled use of an acid or enzyme. Because the sucrose bond is already broken, some beekeepers consider it slightly easier for bees to process than an equivalent sucrose syrup, and commercial invert syrups also resist crystallising in storage better than a home-mixed sucrose syrup can. It's typically bought ready-made from beekeeping suppliers rather than produced at home, and is used at similar concentrations and for similar purposes as standard syrup.

Made-up syrup should be used within a few weeks and stored in clean, sealed containers out of direct sunlight, since it can ferment or grow mould, especially at lighter concentrations. Any syrup that smells sour, looks cloudy, or shows signs of mould should be discarded rather than fed. Preparing syrup in batches sized to what will actually be used shortly avoids most storage problems altogether.